What great trouble the boy had his father to quit smoking!A. persuadedB. persuadeC. to per

问题补充：

What great trouble the boy had his father to quit smoking!

A. persuaded

B. persuade

C. to persuade

D. persuading

答案：

A. persuaded

B. persuade

C. to persuade

(答案→)D. persuading

解析：考查固定结构。固定结构:have some trouble (in) doing sth做某事有困难；本题只是把trouble提前，后面使用定语从句，关系代词知道trouble作为had的宾语，那么横线上所填应该是D。故D正确。