定义A－B = {x| x A，且x B}，若A =" {2," 4, 6, 8, 10}，B =" {1," 4, 8}，则A－B等于
(2)      

A．{4, 8}

B．{1, 2, 6, 10}

C．{1}

D．{2, 6, 10}