单项选择题

Questions 18 to 20 are based on the following passage. At the end of the passage, you will be given 15 seconds to answer the questions.
By citing the remarks of Diogenes, the speaker wants to say that

A.we need to learn the skills of talking.
B.listening is easier than talking.
C.it is important to be an attentive listener.
D.we should talk less and do mor