I wondered what difficulty he had the plan.A. to carry outB. carrying outC. carried outD.

问题补充：

I wondered what difficulty he had the plan.

A. to carry out

B. carrying out

C. carried out

D. with carrying out

答案：

A. to carry out

(答案→)B. carrying out

C. carried out

D. with carrying out

解析：考查非谓语动词。句中he had the plan作定语，这里考查短语have difficulty (in) doing sth.做某事有可能。句意：我想知道他执行这个计划有什么困难。故B正确。