---You have made great progress in your English study haven’t you?- Yes but much .A.

问题补充：

---You have made great progress in your English study, haven’t you?

--- Yes, but much .

A. remains to do

B. is remained to do

C. remains to be done

D. is remained to be done

答案：

A. remains to do

B. is remained to do

(答案→)C. remains to be done

D. is remained to be done

解析：考查remain的用法。remain是不及物动词，故排除B、D,根据意思，很多事情有待于被解决，故选C。