题目

For the Japanese festival Obon, peoplego to clean graves and light incense in memory of their ancestors. 答案：【1】should/ought to设O是坐标原点，点M的坐标为（2，1）．若点N（x，y）满足不等式组，则使得取得最大值时点N个数为（ ）A．1个B．2个C．3个D．无数个