I didn't know what to do, but then an idea suddenly ________ to me.

问题描述:

I didn't know what to do, but then an idea suddenly ________ to me.
a. happened
b. emerged
c. appeared
d. occurred
为什么是D 其他为什么不可以呢

happened发生,emerged形成,appeared出现,occurrto是固定搭配