A、In words. B、By eye contact. C、By clapping hands. D、By raising hand. C该题问面对演讲者的问题，听众如何互动，在录音最后，演讲者让听众通过拍手的方式来表示yes，故C为正确答案。

Moderator:
    Faced with a wide variety of goods in the shopping mall, have you ever been crazy for the choice overload problem? Today, we are honored to have Sheena Zyengar. business professor from Columbia University, to give us a lecture on how to make choice easier.
Sheena Zyengar:
    Thank you!
    Do you know how many choices you make in a typical day? Do you know how many choices you make in a typical week? I recently did a survey with over 2,000 Americans, and the average number of choices that the typical American reports making is about 70 in a typical day.
    There was also recently a study done with CEOs in which these scientists followed CEOs around for a whole week. And they simply documented all the various tasks that these CEOs engaged in and how much time they spent engaging in making decisions related to these tasks. And they found that the average CEO engaged in about 139 tasks in a week. Each task was made up of many, many sub-choices of course. 50 percent of their decisions were made in nine minutes or less. Only about 12 percent of the decisions did they make an hour or more of their time.
    Think about your own choices. Do you know how many choices make it into your nine minute category versus your one hour category? How well do you think you’re doing at managing those choices?
    Today I want to talk about one of the biggest modern day choosing problems that we have, which is the choice overload problem. I want to talk about the problem and some potential solutions.
    Now as I talk about this problem, I’m going to have some questions for you and I’m going to want to know your answers. So when I ask you a question, since I’m blind, only raise your hand if you want to bum off some calories. Otherwise, when I ask you a question, and if your answer is yes, I’d like you to clap your hands. So for my first question for you today: Are you guys ready to hear about the choice overload problem?
23 What is the purpose of the survey done with CEOs?
24 What is the focus of Professor Sheena Iyengar’s speech?
25 How will the audience respond to the speaker’s question if their answer is "yes"?