题目

设全集U=R,集合M={x|x≤1或x≥3},集合P=，且UM≠，则实数k的取值范围是（  ）                                                                                                       A. 0＜k＜3    B. k≤0 或k≥3   C. k<3    D. k>0 答案：A 

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