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Study hard, ________ you're sure to have a good result in the exam!

A. but            B. and            C. for             D. or

 Study hard, ________ you're sure to have a good result in the exam!

A. but　　　B. and　　　C. for　　　D. or

 Study hard , _______ you’re sure to have a good result in the exam !

    A. but                   B. and                  C. for                   D. or

Study hard, ________ you're sure to have a good result in the exam.

A. and

B. but

C. for

D. or

Study hard，          you're sure to have a good result in the exam!

A．but                      B．and                      C．for                        D．or