–I find Chinese people are helpful when traveling around China. –You’re right. I like whe

问题补充：

–I find Chinese people are helpful when traveling around China.

–You’re right. I like when people are friendly and helpful.

A. that

B. them

C. one

D. it

答案：

A. that

B. them

C. one

(答案→)D. it

解析：考查代词。it是形式宾语，指代when引导的时间状语从句。