finish their task ahead of time the students worked harder and harder.A. In order toB. So

问题补充：

finish their task ahead of time, the students worked harder and harder.

A. In order to

B. So as to

C. As to

DIn order not to

答案：

(答案→)A. In order to

B. So as to

C. As to

D. In order not to

解析：词义辨析题。In order to“为了”用在句首或句中；So as to“为了”不能位于句首。句意：为了提前完成任务学生们越来越努力。