一条物理链路可以划分成（）。

A.2⁸个VC
B.2¹²个VC
C.2⁸~2¹²个VC
D.2¹⁶个VC

A.IP over ATM
B.IP over SDH
C.IP over DWDM
D.IP over ATM和IP over SDH

A.IP over ATM
B.IP over SDH
C.IP over DWDM
D.IP over ATM和IP over SDH