In _____ method, the word is written to the block in both the cache and main…

Answer: Write through

Explanation:

• In the write-through method, a write operation updates both the cache and main memory simultaneously.

• Advantage: Keeps main memory consistent with the cache, which simplifies coherence and correctness.

• Disadvantage: Slower write performance because every write also updates main memory.

• Contrast with write-back: write-back updates only the cache and writes modified blocks to main memory later (on eviction) using a dirty bit. That is faster for writes but can leave main memory temporarily stale.

• Other choices are incorrect because they do not describe updating cache and main memory in parallel: write-protected prevents writes, and direct mapping is a placement scheme, not a write policy.