Cheating is strictly forbidden in this important exam, and students bring any reference books into their classrooms, cell phones included.
A. will not
B. should not
C. mustn’t
D. need not
网友回答
A. will not
B. should not
(答案→)C. mustn’t
D. need not
解析：句意：作弊在这样重要的考试中是严格禁止的，学生不能带参考书进教室包括手机。根据句意用mustn’t“禁止”，其他三个选项：will not不会，shouldn’t不应该，needn’t不必，语气都不对。选C。