. “You ___ not be too careful in the exam. Do and check your papers carefully and you ____ not take your papers out of the examination room after the exam.” the teacher told us before the exam.

A．must; should

B．can; shall

C．must; shall

D．can; could

迈克尔·波特提出了最具影响力的战略分析模型是( )。

A．五力模型
B．PETS模型
C．SWOT模型
D．CAMEL模型