This table represents a quadratic function. Х
у
1
3
3
-3
5
-5
7
-3
9
3
Which statement about this function is true?
A.
The value of a is positive, so the vertex is a maximum.
B.
The value of a is positive, so the vertex is a minimum.
C.
The value of a is negative, so the vertex is a maximum.
D.
The value of a is negative, so the vertex is a minimum.