Her friend did everything in his to help with her business.A. energyB. power C. strength

问题补充：

Her friend did everything in his to help with her business.

A. energy

B. power

C. strength

D. force

答案：

A. energy

(答案→)B. power

C. strength

D. force

解析：考查名词：A. energy精力B. power权力C. strength力气D. force武力，句意：她的朋友做了权力范围之内的一切来帮助她的生意。选B。