Cindy shut the door heavily and burst into tears. No one in the office knew she was so ang

问题补充：

Cindy shut the door heavily and burst into tears. No one in the office knew she was so angry.

A. where

B. whether

C. that

D. why

答案：

A. where

B. whether

C. that

(答案→)D. why

解析：句意：Cindy狠狠的关上门哭了起来，办公室里没人知道他为什么如此生气。where 在哪儿；whether 是否；that 引导陈述句的宾语从句.