We’d say that never before so moving a film as After Shock.A．we had seen \x05B．had we seen\x05C．we have seen \x05D．have we seen为什么不是 B而是D

We’d say that never before so moving a film as After Shock.
A．we had seen \x05B．had we seen\x05C．we have seen \x05D．have we seen
为什么不是 B而是D

从倒装结构看,BD都行
但显然 After Shock这部电影 是之前看的,那么 在看这部电影之前,从来没看过如此感人的电影,就是过去的过去了,所以用过去完成时.

强调对现在造成的结果或影响，意思是 到现在为止还没有看过 所以是D。
当句中没有出现明确的过去时间时，不能看作是对过去的影响，所以不能用B过去完成时。