After her son died in a car accident, the old lady would sit at the window, ______ out and _______ in thought.    

A．looked; lost

B．looking; losing

C．looked; losing

D．looking; lost

先天性胆总管囊肿发病机制中最新学说是（）

A.胚胎期胆道上皮增生

B.先天性神经节细胞缺乏

C.宫内胆管性肝炎

D.胰胆管解剖畸形，使胰液向胆道反流所致

E.宫内缺氧