On the chairs         , who had come here for this job interview.

A．did three graduates sit

B．sat three graduates

C．three graduates sat

D．sitting three graduates

设置伸缩缝的建筑物，其基础部分仍连在一起的原因是( )。

A．基础受温度变化影响小

B．伸缩缝比沉降缝窄

C．基础受房屋构件伸缩影响小

D．沉降缝已将基础断开