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若集合A={3,a2},B={2,4},则“a=2”是“A∩B={4}”的( )...
若集合A={3,a2},B={2,4},则“a=2”是“A∩B={4}”的( )
A.充分不必要条件
B.必要不充分条件
C.充要条件
D.既不充分也不必要条件
考点分析:
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