Function f is represented by the equation given below.
f(x)=x^2-5x+6
Function g has a vertex at (2,4) and the parabola opens downwards.

Which of the following statements is true?
A.) The y-intercept of function f is greater than the y-intercept of function g.
B.) The minimum of function g is at (2,4).
C.) The minimum of function f is at (-5,6).
D.) The y-intercept of function f is less than the y-intercept of function g.