Elephant have their own way to tell the shape of an object and it is rough or smooth

问题描述:

Elephant have their own way to tell the shape of an object and it is rough or smooth
A / B that C as D which
为什么选B,不选D
可以翻译一下此句吗

定语从句,具体说明the shape of an object .that指的是具体内容,而不是哪一个,排除D