Computer Science Practice MCQ Question and Answer

Which of the following is the brain of the computer?

A. a) Central Processing Unit

B. b) Memory

C. c) Arithmetic and Logic unit

D. d) Control unit

Correct answer is: A. a) Central Processing Unit

a) Central Processing Unit (CPU).

The CPU is often referred to as the "brain" of the computer because it's the central component responsible for processing instructions and carrying out the core operations of the system. Here's a breakdown of why the other options are important but not quite the brain:

b) Memory: Memory stores data and instructions that the CPU needs to access, but it doesn't perform the actual processing. It's more like the computer's short-term memory or storage.

c) Arithmetic and Logic Unit (ALU): The ALU is an essential part of the CPU that performs mathematical and logical operations. It's like the calculator within the brain, but it doesn't make decisions or control the overall flow of execution.

d) Control Unit (CU): The CU is another crucial part of the CPU that fetches instructions from memory, decodes them, and directs the ALU to perform the necessary operations. It's like the conductor of the orchestra, but it still relies on the CPU as a whole to function.

The CPU: The Mastermind

The CPU is the central processing unit that combines the functionalities of the control unit and the ALU. It fetches instructions, decodes them, controls the flow of data, and performs the necessary calculations and operations. It's the decision-maker and the engine that drives the computer's processing power.

While memory, ALU, and CU all play vital roles, the CPU acts as the central coordinator and processing unit, making it the most fitting analogy for the computer's brain.

Which of the following computer language is written in binary codes only?

A. a) pascal

B. b) machine language

C. c) C

D. d) C#

Correct answer is: B. b) machine language

b) machine language.

Here's why:

Machine language is the only language computers understand natively. It consists entirely of binary code, sequences of 0s and 1s, which directly correspond to the computer's internal operations.

Pascal, C, and C# are all high-level programming languages. They are much easier for humans to read and write than machine code. However, they need to be translated into machine code by a compiler or interpreter before the computer can execute them.

Why Machine Language is Special

Machine language is the most fundamental language of computers. Each instruction in machine code corresponds to a specific operation the computer's hardware can perform. While it's efficient for the computer, it's very difficult and error-prone for humans to work with directly.

The Role of Higher-Level Languages

High-level languages like Pascal, C, and C# provide a more human-friendly way to write programs. They use keywords, variables, and control flow structures that are easier to understand than raw binary code. These languages then rely on compilers or interpreters to convert the code into machine code that the computer can execute.

In summary, while machine language is the native tongue of computers, high-level languages offer a more practical and user-friendly way for humans to interact with them.

Which of the following language does the computer understand?

A. a) Computer understands only C Language

B. b) Computer understands only Assembly Language

C. c) Computer understands only Binary Language

D. d) Computer understands only BASIC

Correct answer is: C. c) Computer understands only Binary Language

c) Computer understands only Binary Language.

Here's a breakdown of why the other options are incorrect:

a) Computer understands only C Language: C is a popular high-level programming language, but computers need this code translated into machine language (binary) before they can execute it.

b) Computer understands only Assembly Language: Assembly is closer to machine code than C, but it still needs to be assembled into binary for the computer to understand.

d) Computer understands only BASIC: BASIC is another high-level language that requires translation into binary for the computer to process.

Why Binary?

Computers are essentially electrical machines. They use electrical circuits with switches that can be either on (representing 1) or off (representing 0). By cleverly arranging these on/off states (bits), the computer can represent instructions, data, and all the information it needs to function.

Higher-Level Languages: Making Life Easier

While binary is the fundamental language of computers, it's incredibly tedious and error-prone for humans to write programs directly in binary. That's why we have higher-level languages like C, Python, Java, etc. These languages use more human-readable syntax, and then compilers or interpreters translate them into machine code that the computer can understand.

In essence, binary is the only language the computer truly understands, but higher-level languages make it much more convenient for us to interact with computers.

What is the full form of CPU?

A. a) Computer Processing Unit

B. b) Computer Principle Unit

C. c) Central Processing Unit

D. d) Control Processing Unit

Correct answer is: C. c) Central Processing Unit

Explanation: CPU stands for Central Processing Unit. CPU is the part of a computer system that is mainly referred as the brain of the computer.

Which of the following is the correct definition of Computer?

A. a) Computer is a machine or device that can be programmed to perform arithmetical or logic operation sequences automatically

B. b) Computer understands only binary language which is written in the form of 0s & 1s

C. c) Computer is a programmable electronic device that stores, retrieves, and processes the data

D. d) All of the mentioned

Correct answer is: D. d) All of the mentioned

That's right! The correct definition of computer is:

d) All of the mentioned

Here's why all the options contribute to a comprehensive definition of a computer:

a) Computer is a machine or device that can be programmed to perform arithmetical or logic operation sequences automatically: This accurately describes the core functionality of a computer. It can follow a set of instructions (program) to perform calculations and make logical decisions.

b) Computer understands only binary language which is written in the form of 0s & 1s: This is true at the hardware level. Internally, computers operate using a binary system where all data and instructions are represented by combinations of 0s and 1s.

c) Computer is a programmable electronic device that stores, retrieves, and processes data: This highlights several crucial aspects of computers:

Programmable: They can be instructed to perform different tasks based on the software they run.

Electronic: They use electronic circuits and components to process information.

Data storage and retrieval: They can store data (information) for later use and retrieve it when needed.

Data processing: They can manipulate and transform data according to the program's instructions.

Therefore, a complete definition of a computer should encompass all these elements. It's a programmable electronic device that understands binary language, stores and retrieves data, and processes information according to programmed instructions