780B设备中，分布有四个DCC通道的槽位有（）。
A.环1-环4
B.环5-环8
C.环1-环2
D.环3-环9
参考答案：C
Tom kept quiet about the accident lose his job.
A．so not as to
B．so as not to
C．so as to not
D．not so as to
RGB色系
