The idiom “Take someone’s word for it” means to accept what someone says as true without requiring additional proof or verification. It signifies a level of trust in the speaker's honesty, accuracy, or knowledge regarding a particular matter. When you take someone's word for it, you are essentially relying on their statement as fact.
Therefore, A: Believe what someone says is the accurate meaning. B: Disbelieve is the direct opposite, implying a lack of trust or a need for evidence. C: Alleged person refers to someone accused of an offense but not yet proven guilty, which is entirely unrelated to the concept of believing a statement. This idiom is fundamental to understanding trust in communication.