Antonio Has Just Finished Giving a Presentation and Is Answering

Antonio has just finished giving a presentation and is answering audience questions when one of his listeners asks him something he doesn't know how to answer. How should Antonio respond?

A) He should come up with an answer that sounds plausible.
B) He should state that he doesn't know the answer and invite others to share their ideas.
C) He should say, "That's a silly question," and move on to the next person.
D) He should act like he didn't hear the question and move on to the next person.
E) He should provide an answer to a question he does know.