They believed,and〔〕did we,→

问题描述:

They believed,and〔〕did we,→
→that these modern paintings collected in the Shanghai Art Gallery were as valuable as those in the Museum.
选项是:A.that B.which C.neither D.so
请告诉我选A的原因.

选D,so + 助动词 + 主语 表示“...也是”
而so + 主语 + 助动词 表示“...的确如此”
楼主下面那句话跟题目有关系吗?