单选题It was a great _____

问题补充：

单选题Itwasagreat_____forhimtobepleasanttopeoplehedidn like.A.attemptB.troubleC.powerD.effort

答案：

D解析effort (作可数名词用) 努力的尝试：Does it require a great effort of will to give up smoking? (戒烟需要坚强的毅力吗？)