← MES Jr. Grade
Past Questions
Match the following. (P) SMTP (1) Application layer (Q) BGP (2) Transport layer (R) TCP (3) Data link layer (S) PPP (4) Network layer (5) Physical layer
A)
P-2, Q-1. R-3, S-5
B)
P-1, Q-4, R-2, S-3
C)
P-1, Q-4, R-2, S-5
D)
P-2, Q-4, R-1, S-3
Based on established principles in Computer Science & Engineering, the correct and most appropriate choice is 'P-2, Q-1. R-3, S-5' (Option A).
ER Diagram represents a overall __________ of a Database graphically.
A)
Physical Structure
B)
Logical Structure
C)
Domain Structure
D)
Architectural Representation
Based on established principles in Computer Science & Engineering, the correct and most appropriate choice is 'Logical Structure' (Option B).
Statistical software quality assurance in software engineering involves
A)
using sampling in place of exhaustive testing of software.
B)
surveying customers to find out their opinions about product quality.
C)
tracing each defect to its underlying cause, isolating the vital few causes, and moving to correct them.
D)
tracing each defect to its underlying causes, and using the Pareto principle to correct each problem found.
Based on established principles in Computer Science & Engineering, the correct and most appropriate choice is 'tracing each defect to its underlying causes, and using the Pareto principle to correct each problem found.' (Option D).
All the modules of the system are integrated and tested as complete system in the case of
A)
Bottom up testing
B)
Top-down testing
C)
Sandwich testing
D)
Big-Bang testing
Based on established principles in Computer Science & Engineering, the correct and most appropriate choice is 'Top-down testing' (Option B).
Consider the following transactions with data items A and B initialized to zero: T1: read (A) ; read (B) ; if A = 0 then B : = B + 1 ; write (B) ; T2: read (B) ; read (A) ; if B = 0 then A : = A + 1 ; write (A) ; Any non-serial interleaving of T1 and T2 for concurrent execution leads to
A)
A serializable schedule
B)
A schedule that is not conflict serializable
C)
A conflict serializable schedule
D)
A schedule for which a precedence graph cannot be drawn
Based on established principles in Computer Science & Engineering, the correct and most appropriate choice is 'A schedule for which a precedence graph cannot be drawn' (Option D).
__________ function is used to find the number of values in a column.
A)
SUM
B)
COUNT
C)
ADD
D)
AVG
Based on established principles in Computer Science & Engineering, the correct and most appropriate choice is 'COUNT' (Option B).
Which one of the following uses UDP as the transport protocol?
A)
HTTP
B)
Telnet
C)
DNS
D)
SMTP
Based on established principles in Computer Science & Engineering, the correct and most appropriate choice is 'DNS' (Option C).
In __________ transmission, the channel capacity is shared by both communicating devices at all times.
A)
simplex
B)
half-duplex
C)
full-duplex
D)
half-simplex
Based on established principles in Computer Science & Engineering, the correct and most appropriate choice is 'full-duplex' (Option C).
Basis path testing falls under
A)
system testing
B)
white box testing
C)
black box testing
D)
unit testing
Based on established principles in Computer Science & Engineering, the correct and most appropriate choice is 'black box testing' (Option C).
The optimizer that explores the space of all query-evaluation plans is called
A)
Cost-based
B)
Plan-based
C)
Estimate-based
D)
Count-based
Based on established principles in Computer Science & Engineering, the correct and most appropriate choice is 'Plan-based' (Option B).
Which one of the following is NOT desired in a good Software Requirement Specifications (SRS) document?
A)
Functional Requirements
B)
Non-Functional Requirements
C)
Goals of Implementation
D)
Algorithms for Software Implementation
Based on established principles in Computer Science & Engineering, the correct and most appropriate choice is 'Algorithms for Software Implementation' (Option D).
What is the maximum size of data that the application layer can pass on to the TCP layer below?
A)
Any size
B)
2^16 bytes-size of TCP header
C)
2^16 bytes
D)
500 bytes
Based on established principles in Computer Science & Engineering, the correct and most appropriate choice is '500 bytes' (Option D).
Which of the following is true in case of Oblique Projections? I. Parallel projection rays are not perpendicular to the viewing plane. II. Parallel lines in space appear parallel on the final projected image. III. Used exclusively for pictorial purposes rather than formal working drawings. IV. Projectors are always perpendicular to the plane of projection.
A)
I and IV only
B)
I, II and III only
C)
II and III only
D)
IV only
Let's analyze each statement regarding Oblique Projections:
1. **Statement I: Parallel projection rays are not perpendicular to the viewing plane.** This is TRUE. By definition, an oblique projection is a type of parallel projection where the projectors (projection rays) strike the projection plane at an angle other than 90 degrees. If they were perpendicular, it would be an Orthographic projection.
2. **Statement II: Parallel lines in space appear parallel on the final projected image.** This is TRUE. Oblique projection is a subset of Parallel Projection. A fundamental property of all parallel projections is that parallel lines in 3D space remain parallel in the 2D projection.
3. **Statement III: Used exclusively for pictorial purposes rather than formal working drawings.** This is TRUE. Because oblique projections distort the depth (the receding axis is scaled), they are not suitable for precise engineering measurements or formal working drawings (which use Orthographic projections). They are used for quick sketches or pictorial representations (like Cavalier or Cabinet projections).
4. **Statement IV: Projectors are always perpendicular to the plane of projection.** This is FALSE. This is the definition of Orthographic projection. In Oblique projection, projectors are specifically NOT perpendicular to the plane.
Since statements I, II, and III are correct and statement IV is incorrect, the correct option is 'b'.
What is true about a class and a structure?
A)
A class contains both variables and functions but a structure can contain variables only.
B)
The data items inside a structure are private by default but inside a class pubic by default.
C)
A class and structure are not similar at all.
D)
None of the above
To determine the correct answer, we must analyze the properties of classes and structures, specifically in the context of C++ (where both exist and are most frequently compared in CSE exams):
1. Analysis of Option (a): 'A class contains both variables and functions but a structure can contain variables only.' This is FALSE. In C++, a `struct` is almost identical to a `class`; it can contain both member variables (data members) and member functions (methods).
2. Analysis of Option (b): 'The data items inside a structure are private by default but inside a class public by default.' This is FALSE. It is actually the opposite: in a `struct`, members are **public** by default, whereas in a `class`, members are **private** by default.
3. Analysis of Option (c): 'A class and structure are not similar at all.' This is FALSE. They are very similar; the primary difference is the default access specifier (public for struct, private for class).
Since options (a), (b), and (c) are all technically incorrect, the correct choice is (d) None of the above.
What is the output of the below program? #include<iostream> using namespace std; int main() { enum {red, blue=5, GREEN}; cout<<red<<“ “<<GREEN; }
A)
0 3
B)
0 8
C)
0 6
D)
0 2
In C++, an enumeration (enum) assigns integer constants to names. The rules for assignment are as follows:
1. If the first element of an enum is not explicitly initialized, it is assigned the value 0. Therefore, 'red' = 0.
2. If an element is explicitly initialized, it takes that specific value. Therefore, 'blue' = 5.
3. If an element follows another element and is not explicitly initialized, it is assigned the value of the previous element plus one. Therefore, 'GREEN' = blue + 1 = 5 + 1 = 6.
The program outputs 'red' and 'GREEN', which results in '0 6'.
Comparing with options:
- Option a (0 3) is incorrect because it assumes GREEN is the 3rd element (index 2) without considering the explicit value of blue.
- Option b (0 8) is incorrect as there is no logic leading to 8.
- Option d (0 2) is incorrect as it assumes a simple 0, 1, 2 sequence.
What occurs within the context of the producer-consumer cooperation problem?
A)
The producer and consumer operate autonomously without utilizing a buffer for their interaction.
B)
The consumer is responsible for adding data to the buffer, while the producer takes on the task of removing it.
C)
The producer is responsible for adding data to the buffer, while the consumer undertakes the task of removing it.
D)
The producer and consumer processes run concurrently, given a shared buffer.
The Producer-Consumer problem (also known as the Bounded-Buffer problem) is a classic synchronization problem in Operating Systems.
1. **Definition of Roles**: In this scenario, the 'Producer' is a process that generates data and places it into a shared storage area (the buffer). The 'Consumer' is a process that removes that data from the buffer to process it.
2. **The Buffer**: The buffer acts as a queue. If the buffer is full, the producer must wait; if the buffer is empty, the consumer must wait.
3. **Evaluating Options**:
- Option (a) is incorrect because the interaction fundamentally relies on a buffer to decouple the production and consumption rates.
- Option (b) is incorrect because it reverses the roles of the producer and consumer.
- Option (c) is correct as it accurately describes the fundamental roles: Producer adds, Consumer removes.
- Option (d) is a true statement about the environment (they do run concurrently with a shared buffer), but it describes the *setup* rather than what *occurs* (the action/responsibility) within the context of the problem's logic. In the context of multiple-choice questions on this topic, the functional definition of the roles (Option c) is the primary answer.
Which of the following features does not belong to describe pure OOP?
A)
Classes must be used compulsorily
B)
Inheritance
C)
Function Overloading
D)
Data may or may not be declared using object
A 'Pure Object-Oriented Programming' language is one where everything is treated as an object. In such a language, it is impossible to declare data or functions outside of a class/object.
1. Option (a) 'Classes must be used compulsorily' is a characteristic of pure OOP because you cannot have standalone functions or variables.
2. Option (b) 'Inheritance' is one of the core pillars of OOP (alongside Encapsulation, Polymorphism, and Abstraction).
3. Option (c) 'Function Overloading' is a form of compile-time polymorphism, which is a key feature of OOP.
4. Option (d) 'Data may or may not be declared using object' describes a 'Hybrid' or 'Multi-paradigm' language (like C++ or Java, where you can have static variables or primitive types). In a Pure OOP language (like Smalltalk), data MUST be declared as part of an object. Therefore, the possibility of declaring data without an object contradicts the definition of pure OOP.
What is the most used computer operating system?
A)
Linux
B)
Windows
C)
Chrome OS
D)
Android
To determine the 'most used' operating system, one must consider the total number of active devices globally across all platforms (mobile, desktop, and server).
1. **Android (Option d):** Android is a mobile operating system based on the Linux kernel. Due to the massive proliferation of smartphones and tablets globally, Android holds the largest market share of all operating systems combined. Statistically, it consistently ranks as the most installed OS worldwide.
2. **Windows (Option b):** While Windows is the dominant operating system for desktop and laptop computers, its total user base is smaller than the combined global mobile user base of Android.
3. **Linux (Option a):** Linux is the most used OS for servers, supercomputers, and embedded systems, but it has a relatively small market share on consumer desktops.
4. **Chrome OS (Option c):** Chrome OS has a niche market, primarily in the education sector, and is significantly less common than the other three options.
Therefore, when considering all computing devices (including mobile), Android is the most used operating system.
What does an operating system do
A)
An interface that regulates hardware and software programs
B)
A hardware device
C)
A program that operates the hardware devices
D)
A program that operates the software devices
An Operating System (OS) is a system software that acts as an intermediary or interface between the computer user/application software and the computer hardware. Its primary roles include resource management (CPU, memory, I/O devices) and providing a platform for application software to run.
Analysis of options:
- Option (a) is correct because the OS regulates how software programs access hardware resources, ensuring efficiency and preventing conflicts.
- Option (b) is incorrect because an OS is software, not a physical hardware device.
- Option (c) is partially true in a narrow sense, but 'operates the hardware devices' is an incomplete description; the OS manages them rather than just 'operating' them, and it must also manage software.
- Option (d) is incorrect because 'software devices' is a technically inaccurate term; software consists of programs and data, not 'devices'.
In FIFO page replacement algorithm, when a page must be replaced
A)
oldest page is chosen
B)
newest page is chosen
C)
random page is chosen
D)
none of the mentioned
The FIFO (First-In-First-Out) page replacement algorithm is one of the simplest page replacement strategies used in operating systems to manage memory.
1. **Mechanism**: The algorithm maintains a queue of all pages currently in memory. When a new page needs to be loaded and the memory (frame) is full, the page that has been in memory the longest is the first one to be removed.
2. **Logic**: Since the first page to enter the memory is the 'oldest' in terms of arrival time, it is the first to be replaced, regardless of how often or how recently it has been accessed.
Analysis of options:
- **Option (a) oldest page is chosen**: Correct. This is the definition of FIFO.
- **Option (b) newest page is chosen**: Incorrect. This would be a 'Last-In-First-Out' (LIFO) approach, which is not standard for page replacement.
- **Option (c) random page is chosen**: Incorrect. This describes the 'Random Replacement' algorithm, where a page is picked arbitrarily to avoid the overhead of tracking arrival times.
- **Option (d) none of the mentioned**: Incorrect, as option (a) is correct.
Which specific function enables the provision of a communication facility between client programs?
A)
Monolithic kernel
B)
Microkernel
C)
Hybrid Kernels
D)
Nano Kernels
In a Microkernel architecture, the kernel is stripped of all non-essential components. Most OS services (such as file systems, device drivers, and network stacks) are moved out of the kernel space and into the user space as 'server' programs. Because these services now reside in separate address spaces, they cannot communicate via simple function calls. Therefore, the primary and specific function of a Microkernel is to provide a mechanism for Inter-Process Communication (IPC), which enables the communication facility between client programs and these service providers (servers).
Comparison with other options:
- Monolithic kernel (a): All OS services run in the same kernel address space; they communicate via direct function calls rather than a specialized communication facility.
- Hybrid Kernels (c): A combination of both, but the 'specific function' of providing a communication facility as a core architectural requirement is the defining characteristic of the Microkernel approach.
- Nano Kernels (d): Even smaller than microkernels, focusing on basic hardware abstraction, but the standard academic answer for the provision of communication facilities between user-space services is the Microkernel.
After invoking the destructor of an object
A)
The members of that object cannot be accessed
B)
The members of that object can be accessed only if the object is const
C)
The members of that object can be accessed without problem
D)
All the previous answers are incorrect
In Object-Oriented Programming (specifically C++), a destructor is a special member function that is called when an object goes out of scope or is explicitly deleted. The primary purpose of the destructor is to release resources (like memory or file handles) that the object acquired during its lifetime. Once the destructor has finished executing, the object's lifetime officially ends, and the memory it occupied is considered 'deallocated' or 'invalid'. Attempting to access the members of an object after its destructor has been invoked results in 'Undefined Behavior' (UB). In a logical and architectural sense, the object no longer exists; therefore, its members cannot be accessed.
- Option (b) is incorrect because 'const' qualifiers affect whether a member can be modified, not whether the object exists in memory.
- Option (c) is incorrect because accessing a destroyed object leads to memory corruption or segmentation faults.
- Option (d) is incorrect because option (a) is the logically correct answer in the context of object lifecycles.
Segment replacement algorithms are more complex than page replacement algorithms because
A)
Segments are better than pages
B)
Pages are better than segments
C)
Segments have variable sizes
D)
Segments have fixed sizes
In Operating Systems, Paging and Segmentation are two different memory management schemes.
1. **Paging**: Memory is divided into fixed-size blocks called 'pages' (logical) and 'frames' (physical). Because every page is the same size, replacing one page with another is straightforward; any page can fit into any available frame. The OS only needs to track which frame is free or which page to evict.
2. **Segmentation**: Memory is divided into logical units called 'segments' (e.g., code, data, stack), which have variable sizes based on the actual needs of the program.
**Why Segment Replacement is more complex:**
- **Variable Size**: When a segment needs to be brought into memory, the OS must find a contiguous block of free memory (a 'hole') that is large enough to accommodate that specific segment's size.
- **External Fragmentation**: Because segments vary in size, replacing a small segment with a larger one is not always possible even if the total free memory is sufficient. This leads to external fragmentation.
- **Allocation Strategies**: The OS must implement complex placement algorithms such as First-Fit, Best-Fit, or Worst-Fit, and may need to perform 'compaction' (shuffling memory to create a large enough hole), which is computationally expensive.
Therefore, the variable size of segments makes the replacement and allocation process significantly more complex than the fixed-size replacement used in paging.
Consider the following page reference string: 1 2 3 4 2 1 5 6 2 1 2 3 7 6 3 2 1 2 3 6. For LRU page replacement algorithm with 5 frames, the number of page faults is?
A)
10
B)
14
C)
8
D)
11
Based on established principles in Basic Computer Knowledge, the correct and most appropriate choice is '8' (Option C).
Identify the way to create a dynamic array of pointers (to integers) of size 10 in C++?
A)
int *arr = new int *[10];
B)
int **arr = new int *[10];
C)
int *arr = new int [10];
D)
Not Possible
To create a dynamic array of pointers, we must understand the types involved:
1. The target elements of the array are 'pointers to integers', which have the type `int*`.
2. When we use the `new` operator to allocate an array of a certain type, it returns a pointer to the first element of that array.
3. Therefore, if we allocate an array of `int*`, the return type must be a pointer to an `int*`, which is a double pointer: `int**`.
Breaking down Option (b): `int **arr = new int *[10];`
- `new int *[10]` allocates memory for 10 pointers to integers on the heap.
- `int **arr` declares a pointer to a pointer to an integer, which correctly stores the address of the first element of the allocated array.
Why other options are incorrect:
- Option (a): `int *arr = new int *[10];` is incorrect because it attempts to assign a pointer-to-pointer (`int**`) to a single pointer (`int*`), causing a type mismatch error.
- Option (c): `int *arr = new int [10];` creates a dynamic array of integers, not an array of pointers to integers.
- Option (d): This is possible in C++ using the logic described above.