已知全集U={1,2,3,4,5,6,7},集合A={1,3,5,6},则∁UA等于( )
(A){1,3,5,6} (B){2,3,7}
(C){2,4,7} (D){2,5,7}
C解析:由题意知∁UA={2,4,7}.