Which of the following methods of concluding a speech would most likely encourage a listener to seek further information about the topic?

Concluding a speech by asking a question effectively engages the audience and invites them to think more deeply about the topic. This method fosters critical thinking and curiosity, compelling listeners to explore further information. By posing an unanswered or thought-provoking question, speakers can inspire the audience to seek additional insights, research, or discussions beyond the speech itself, making it an effective strategy for encouraging ongoing interest in the subject matter.

The other methods listed, while they may serve to wrap up a speech or leave an impression, do not actively encourage exploration in the same way. A famous quotation might provide a poignant finish but lacks the immediate prompting for further investigation. Telling a humorous story can entertain and create a positive sentiment but does not typically motivate a desire for further inquiry. Providing a shocking statistic can be impactful and memorable, but it may also leave listeners feeling overwhelmed, thus not promoting the same level of engagement for seeking more information as a question would.