Answer:
The correct option is A.
Explanation:
The vertex form of a parabola is
..... (1)
Where, (h,k) is vertex and a is a constant.
From the given graph it is clear that the vertex of the graph is (3,-7) and y-intercept is (0,2).
Substitute h=3 and k=-7 in equation (1).

The y-intercept is (0,2). So, substitute c=0 and y=2 in the above equation to find the value of a.



Divide both sides by 9.

The value of a is 1.
Substitute a=1, h=3 and k=-7 in equation (1).



The equation of the parabola is
.
Therefore the correct option is A.