题目

已知定义域为R的函数f(x)在区间(8，＋∞)上为减函数，且函数y＝f(x＋8)为偶函数，则( ) A.f(6)>f(7)                                B.f(6)>f(9) C.f(7)>f(9)                                D.f(7)>f(10) 答案：D__________ tired I am, I will try my best to finish the important task.A. No matter what B. No matter howC. No matter when D. No matter where