I looked out and found the ground ____ with white snow

题目

I looked out and found the ground ____ with white snow
A.covered B.is covered
为什么选A．
而不是B被动语态呢?

答案

A 是find＋宾语＋宾语补足语
B 如果是was也可,可以认为I looked out and found （that） the ground was covered with white snow.
但是选项用的时态不对