the equation of a parabola with its vertex at the origin and a focus of (-8,0)
vertex is (0,0), h=0 and k=0
Focus is (-8,0)
Focus is (h+p, k)
We know h=0 and k=0
(0+p, 0) is (-8,0)
p = -8
General form of equation is

h=0, k=0 and p =-8


Answer : option A