It would be a good idea to use an empty room,_______ painted purple,as our temporary lab.
问题描述：
It would be a good idea to use an empty room,_______ painted purple,as our temporary lab.
A.whose walls Bthe walls of which C the walls areD with its walls
答
D
A无谓语,Walls后要有ARE
B同理
C用在这使逗号间成为完整句子,显然这里没说完,只是补充前面