9. 設a與b均為實數,且二次函數f(x)=a(x-1)2 滿足 f(4)> 0, f(5)< 0 。試問下列何者為真?(A)f(0)> 0(B)f(-1)> 0(C)f(-2)> 0(D)f(-3)> 0(E)f(-4)> 0