Central Processing Unit (CPU): The CPU contains all the circuitry primarily responsible for ________ in a stored-program computer.
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Astoring data
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Bkeeping track of time
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Cfetching and interpreting instructions
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DInternet operations
Answer
Correct Answer: fetching and interpreting instructions
Explanation
Introduction / Context:The CPU is the computational heart of a computer. In the von Neumann model, it executes a cycle that repeatedly brings in instructions and performs the operations they specify. Knowing this role clarifies the CPU’s boundary relative to memory and peripherals.
Given Data / Assumptions:
- A stored-program architecture is assumed.
- Instructions and data reside in memory.
- The CPU implements the fetch–decode–execute cycle.
Concept / Approach:The CPU orchestrates fetching instructions from memory, decoding their meaning (operation, operands, addressing modes), and executing them via arithmetic logic unit (ALU), registers, and control logic. While a CPU can temporarily hold data in registers and caches, bulk data storage is the role of memory and secondary storage, not the CPU.
Step-by-Step Solution:
Identify the CPU’s core loop: fetch → decode → execute.Map each step to circuitry: control unit (sequencing), ALU (compute), registers (operands), buses (transfer).Select the phrase that best summarizes this role: “fetching and interpreting instructions.”Exclude answers that describe peripheral or system functions.Verification / Alternative check:Architecture textbooks emphasize instruction processing as the CPU’s defining job; timing and networking are handled by clocks and network stacks elsewhere.
Why Other Options Are Wrong:storing data: main memory and disks handle storage; CPU registers are transient.
keeping track of time: usually a real-time clock or system timer peripheral.
Internet operations: involve NICs, stacks, and OS, not the CPU alone.
Common Pitfalls:Assuming caches make the CPU a storage device; caches are small, transient, and support instruction/data processing rather than long-term storage.
Final Answer:fetching and interpreting instructions