--Can you tell us your parents do at home?.-I often do the dishes and wash the clothes

问题补充：

--Can you tell us your parents do at home?.

---I often do the dishes and wash the clothes.

A. what do you often help

B. if you often help

C. what you often help

D. how do you often help

答案：

A. what do you often help

B. if you often help

(答案→)C. what you often help

D. how do you often help

解析：考查情景交际和宾语从句。“你能告诉我......吗？”“我经常洗碗、洗衣服。”宾语从句要用陈述句语序，排除A、D；选B的话，do缺少宾语，排除B；C项“你经常帮你父母做什么”符合题意。“帮某人做某事”help sb. do sth.。故选C。