Final answer:
Hamlet compares himself to a recorder because he feels that others are playing him like a musical instrument.
Step-by-step explanation:
Hamlet compares himself to a recorder while talking to Rosencratz and Guildenstern. In this comparison, Hamlet is like a recorder because he feels that others are playing him like a musical instrument, option d. Just as a recorder can be played by someone else, Hamlet feels that he is being manipulated and controlled by others.