Answer:
Option: A is the correct answer.
The equation of parabola is:

Explanation:
Clearly we could observe that the parabola opens upward with vertex at (0,0) this means that the general equation of the parabola is:

The focus of parabola is: (0,a) and equation of directrix is: y= -a
From the image provided to us we get:
a=2
and directrix is: y= -2
Hence, the equation of a parabola is: