低血容量休克导致大失血时尿少的原因是（）

A.肾素-血管紧张素-醛固酮系统激活

B.血容量减少引起血管升压素释放

C.血压显著降低引起肾血流量减少

D.晶体渗透压升高引起血管升压素释放

E.肾血流量发生新分布：髓质少皮质多

—Isn't it a surprise that I happened to meet Francis Mafhews at the Christmas party last week?

—If my memory serves me correctly, you ____ each other for exactly two years. [ ]

A. hadn't seen

B. haven't seen

C. didn't see

D. don't see.