Questions 29 to 31 are based on the passage you have just heard.

A．The development goal of UNICEF.
B．Cooperation among developing countries.
C．Economic development and government efforts.
D．People’s awareness of the importance of the problem.

A．Because he is sure that he can get up for the class.
B．Because he has confidence in his economic knowledge.
C．Because he dropped that class two weeks ago.
D．Because he didn’t sign up for that class at the beginning.