Be quick, we have to get to the station before 11:45 _____ we can catch the 12:00 train. [ ]

A. since

B. as soon as

C. after

D. so that

福莱特认为，在形形色色、大大小小的群体之中，最基本的社会群体是( )

A．亲戚群体

B．邻里群体

C．同学群体

D．老乡群体