单项选择题

Which of the following does NOT state how the linguist discovers the nature and the rules of the underlying language system().

A. He has to collect and observe language facts.
B. He has to display and then generalize some similarities of the language facts.
C. He has to formulate some hypotheses about the language structure.
D.He has to deal with the basic concepts, theories, descriptions, models and methods applicable in any linguistic study.