Jack has been working hard and is no doubt that he will do a good job in the entrance exa

问题补充：

Jack has been working hard and is no doubt that he will do a good job in the entrance exam.

A. it

B. what

C. there

D. as

答案：

A. it

B. what

(答案→)C. there

D. as

解析：句意：Jack学习很努力，毫无疑问，他会在考试中取得好成绩。there is no doubt that是固定用法，意思是毫无疑问……，选C。