I wondered what great difficulty he had the plan.A. to carry outB. carrying outC. carrie

问题补充：

I wondered what great 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：句意：我想知道他实施这个计划有多难。这句话用了have difficulty（ in）doing这个词组，意思是“做…很困难”，这里因为是感叹句所以把what great difficulty放在了前面，选B。