【单选题】

Questions 18-20 are based on the following dialogue given by Professor Robert Watson who was answering questions on a radio phone program on the subject of learning a foreign language. You now have 15 seconds to read Questions 18-20. What does "learning to speak" mean, according to the professorA．It means being able to put together the right groups of words and to say them in a reasonably accurate way.

B．It means being able to pronounce correctly.
C．It means having an accurate tone and pronunciation.
D．It means speaking must obey certain grammar..