一道英语单选题,要原因

问题描述:

一道英语单选题,要原因
I am so glad that every thing is going so well as _____
A.plans B.planning C.planned D.to plan

C 我如此开心,因为一切都跟计划的一样好.as it was planned.把it was 省略了,planned直接过去分词做定语