The tour was fantastic in general our car broke down on the way back.A. as　　B. though　　C.

问题补充：

The tour was fantastic in general, our car broke down on the way back.

A. as

B. though

C. whether

D. since

答案：

A. as

(答案→)B. though

C. whether

D. since

解析：句意,上文,总的来说这次旅行太不可思议了,下文在回来的路上我们的车坏了..as意思是由于;though意思是尽管/虽然;wether意思是是否;since意思是自从.故选B.