答案是A
这是独立主格结构.1 him working in London 2 his wife travelling most of the week .
可以改写成“原因状语从句”:
The house seems pretty empty BECAUSE he works in London and his wife travels most of the week.
下面,你把这个句子改写成“独立主格结构”:
As it was raining hard,we had to stay indoors.
--------- It raining hard,we had to stay indoors.