Consider the following statements:1.A microprocessor is a programmable digital device that performs arithmetic and logic operations.2.Control unit generates timing and control signals.3.ALU performs memory read/write operations.Which of the above statements is/are correct?

Correct Answer: A - 1 and 2 only

Quick Concept Explanation

A CPU can be viewed as datapath + control. The datapath contains registers and ALU; the control unit decides which operation occurs and when, including read/write control signals to memory and I/O. Key relation: Conceptual data path: Memory/I-O ↔ buses/registers → ALU → registers; control unit generates READ, WRITE, enable and timing signals.

Exam focus: ALU = compute; control unit = coordinate; registers = fast temporary storage. Common trap: Attributing every CPU action, including memory bus control, to the ALU.

Statement-wise Verification

• Statement 1 - Correct.
  A microprocessor is a programmable digital device that performs arithmetic and logic operations.
  A microprocessor is a programmable digital processor executing arithmetic, logic, data-transfer and control instructions.
• Statement 2 - Correct.
  Control unit generates timing and control signals.
  The control unit decodes instructions and generates sequencing, timing and control signals.
• Statement 3 - Incorrect.
  ALU performs memory read/write operations.
  The ALU does not itself perform memory read/write bus cycles; it operates on data supplied to it, while the control unit/address/data-bus circuitry manages memory transactions.

Core Concept

A CPU can be viewed as datapath + control. The datapath contains registers and ALU; the control unit decides which operation occurs and when, including read/write control signals to memory and I/O.

Formula / Key Relationship

Conceptual data path: Memory/I-O ↔ buses/registers → ALU → registers; control unit generates READ, WRITE, enable and timing signals.

Step-by-Step Check

Functional block definitions validate 1 and 2 and reject 3. Option A.

Why the Other Options Are Wrong

Option B is incorrect because it includes incorrect statement(s) 3 and omits correct statement(s) 1. Option C is incorrect because it omits correct statement(s) 2. Option D is incorrect because it includes incorrect statement(s) 3.

Answer-Key Verification Note

The uploaded provisional key marks C . After independent technical verification, the defensible answer is A . This discrepancy is stated explicitly rather than silently copying the provisional key.

Exam Shortcut / Approach

ALU = compute; control unit = coordinate; registers = fast temporary storage.

Common Mistake

Attributing every CPU action, including memory bus control, to the ALU.

Quick Revision

ALU and Control Unit Functions is linked with CPU Blocks, Processor Architecture and Microprocessors and Microcontrollers. ALU = compute; control unit = coordinate; registers = fast temporary storage.