I have packed the camera.When_____you_____it?A.have;packed B.do;pack C.already D.yet

I have packed the camera.When_____you_____it?
A.have;packed B.do;pack C.already D.yet

When did you pack it?
没答案
这里when相当于一个过去时间状语,得和一般过去式连用
你的支持就是我的动力!

答案是When did you pack it？