单项选择题

You will three dialogues or monologues. Before listening to each one, you will have 5 seconds to read the questions related to it. While listening, answer each question by choosing [A], [B] , [C] or[D]. After listening, you will have 10 seconds to read your answer. You will hear each piece only once. Questions 11～13 are based on the following passage. You now have 15 seconds to read questions 11～13. According to the author, where does the happiness of scientists lie