a)He thinks the police are able to hear the heartbeat he hears.
It's C ;
The narrator confesses to his crime in "The Tell-Tale Heart" because he is overwhelmed by guilt and believes the police can hear the sound of the old man's heartbeat, which symbolizes his mental instability. This moment signifies his complete descent into madness as he can no longer separate reality from his guilt-driven hallucinations. The correct answer is A.
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