假设某消费者对商品X、Y的效用函数是U(X，Y)=5X+5Y，X的价格为10，Y的价格为5，则下列说法正确的是()
A．X、Y是完全互补品B．商品Y的恩格尔曲线的位置与X的价格无关C．商品Y的恩格尔曲线的位置同时取决于X与Y的价格D．以上说法都不正确

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