While shopping people sometimes can't help into buying something they don't really need.

问题补充：

While shopping, people sometimes can help into buying something they don really need.

A. persuade

B. to persuade

C. being persuaded

D. be persuaded

答案：

A. persuade

B. to persuade

(答案→)C. being persuaded

D. be persuaded

解析：考察固定搭配。固定搭配can’t help to do sth不能帮助做某事；can’t help doing sth情不自禁做某事；句意：当人们在购物的时候，人们情不自禁地被说服购买一些他们不是真正需要的东西。根据句意说明使用的是can’t help doing sth“情不自禁做某事”这个结构的被动语态。故C正确。