Final answer:
Hamlet trusts the ghost's word after observing Claudius' guilty reaction during the play that mirrors the ghost's description of his murder, thus validating the suspicion of Claudius' guilt.
Step-by-step explanation:
The question 'Why does Hamlet trust the ghost's word now?' pertains to a key moment in William Shakespeare's play Hamlet, specifically related to Hamlet's growing suspicion towards his uncle, Claudius, after the appearance of his father's ghost. The correct answer to this question is because of Claudius' reaction, which Hamlet interprets during the play-within-a-play scene. This reaction is considered as evidence that aligns with the ghost's accusation, thus confirming the ghost's credibility in Hamlet's eyes.
Hamlet's trust in the ghost solidifies when he observes Claudius' guilty response to the staging of a play that mirrors the way the ghost described his murder. The sudden disturbance of Claudius, who calls for lights and urgently leaves the performance, is a clear indication to Hamlet of his uncle's guilt. This turn of events supports the ghost's account, corroborating the story of Claudius murdering Hamlet's father, and as a consequence, Hamlet feels his suspicion has been validated.