At what point of a projectile motion acceleration and velocity are perpendicular to each other

Options

A. At the point of projection
B. at the point of drop
C. At the top most point
D. Anywhere in between the point of projection and top most point

Explanation

(c) At the top most point of the projectile there is only horizontal component of velocity and acceleration due to gravity is vertially downward so velocity and acceleration are perpendicular to each other.