Stress can be extremely damaging to your health. Exercise _ can reduce its effects.A. at

问题补充：

Stress can be extremely damaging to your health. Exercise, _, can reduce its effects.

A. at the same time

B. while

C. though

D. meanwhile

答案：

A. at the same time

B. while

C. though

(答案→)D. meanwhile

解析：BC属于连词，不能放在句中表转折。A是一个介词短语，也不要放在句中表转折。Meanwhile同时。可以放在句中表转折。句意：压力可能会对你的健康有很大的破坏。同时锻炼可以减少这样的影响。