食管癌最常见的死因是

A．梗阻严重，不能进食，衰竭
B．穿孔，发生相应合并症
C．大呕血
D．转移到肝

— Where did you buy this beautiful skirt?

— It was in the shop ______ my mother is working.

A．that

B．which

C．where

D．what