The young couple couldn’t afford a new house. they wouldn’t have bought an old one.A. Ho

问题补充：

The young couple couldn’t afford a new house. , they wouldn’t have bought an old one.

A. However

B. Otherwise

C. Therefore

D. Instead

答案：

A. However

(答案→)B. Otherwise

C. Therefore

D. Instead

解析：连词副词辨析。A然而（前后都有逗号隔开）；B否则，要不然；C因此；D代替，而不是；句意：这对年轻的夫妻买不起一栋新的房子，要不然，他们也不会买一栋旧房子了。根据句意说明B正确。