Answer
a. C
b. A
c. D
d. B
Work Step by Step
$$y=a(x-h)^2+k$$
If a is positive, the parabola opens up.
If a is negative, the parabola opens down.
Therefore, parabolas A and B open up, and parabolas C and D open down.
The equations are in vertex form.
Graph a has (-4,2) as its vertex.
Graph b has (-2,4) as its vertex.
Graph c has (-4,2) as its vertex.
Graph d has (-2,4) as its vertex.
Knowing this, we can see which graph matches to which equation.