【单选题】

Questions 14 to 17 are based on the following passage.At the end of the conversation, you will be given 20 seconds to answer the questions.

Now listen to the passage.
In USC, to be a T.A．, one should______.A、score high in the speaking part of TOEFL
B．come from anEnglish-speaking country
C．pass a language proficiency test
D．be capable of speaking goodEnglish