设全集U={1，2，3,  4，5,  6，7，8}，集合S="{1," 3, 5}, T="{3," 6}，则Cu(SUT)="(     " )

A．

B．{1, 3，5, 6}

C．{2, 4，7, 8}

D．{2, 4，6, 8}