The computer needs to process each instruction with the following sequence of steps:
A. Calculate the effective address
B. Fetch the instruction from memory
C. Decode the instruction
D. Fetch the operands from memory
E. Execute the instruction
Choose the correct answer from the options given below:

Correct option is C

The sequence of steps for processing an instruction in a computer can be broken down into multiple stages. Let's go through these steps in order, starting with the initial fetch of the instruction and ending with its execution.
The correct sequence for processing an instruction is as follows:
B. Fetch the instruction from memory: The first step is to fetch the instruction from the computer's memory. The instruction is stored in memory, and the CPU retrieves it to begin processing. The Program Counter (PC) typically points to the memory location of the next instruction to be executed. Once the instruction is fetched, the PC is updated to point to the next instruction.
C. Decode the instruction: After fetching the instruction, the next step is to decode it. The CPU's Control Unit (CU) interprets the binary code of the instruction to understand what operation needs to be performed. This step also identifies which registers or memory locations need to be accessed and how the operands should be handled. The instruction is split into parts, such as the opcode (operation code) and the operand (data to be operated on).
A. Calculate the effective address: If the instruction involves accessing data from memory (for example, in the case of a load or store operation), the effective address of the operand(s) needs to be calculated. This involves determining the address of the memory location from which the operands are to be fetched or to which they are to be stored. Addressing modes (such as direct, indirect or indexed addressing) may be used to calculate the effective address.
D. Fetch the operands from memory: After calculating the effective address, the CPU fetches the operands from memory. The operands are the data that the operation will act upon. These operands may be values that are stored in memory or in CPU registers. This step involves accessing memory and loading the operands into registers for use in the next step.
E. Execute the instruction: Finally, the CPU executes the instruction using the operands that were fetched. The Arithmetic Logic Unit (ALU) or other execution units perform the operation specified by the instruction. This can be arithmetic (e.g., addition, subtraction), logical (e.g., AND, OR), or control operations (e.g., jump, compare).
Correct Sequence of Steps:
The correct order for processing an instruction is:
1. B. Fetch the instruction from memory
2. C. Decode the instruction
3. A. Calculate the effective address
4. D. Fetch the operands from memory
5. E. Execute the instruction
Information Booster:
1. Instruction Fetch: The process starts with fetching the instruction from memory using the Program Counter (PC), which tracks the address of the next instruction to be executed.
2. Instruction Decode: The CPU decodes the instruction to understand which operation is to be performed, which addresses need to be accessed, and what kind of operands are involved.
3. Effective Address Calculation: In cases of memory access, the address of the operand is calculated, which may involve additional addressing modes.
4. Operand Fetch: Once the effective address is known, the operands are fetched from memory or registers.
5. Execution: The final step where the CPU performs the operation specified by the instruction, using the operands.
Additional Knowledge:
· Program Counter (PC): The PC plays a crucial role in the instruction fetch cycle. After each instruction fetch, the PC is updated to point to the next instruction.
· Control Unit (CU): The CU interprets and decodes the instruction to determine the operation. It then sends signals to the appropriate components (e.g., ALU, memory) to execute the operation.
· Addressing Modes: Different instructions may use different addressing modes (like direct, indirect or indexed) to calculate the effective address of operands.