Answer:
b. on the horizon
Explanation:
The vanishing point indicates the convergence of parallel lines. Parallel lines seem to approach each other as they move apart, and a vanishing point is the reference that indicates this convergence of lines in the same direction. Linear perspective is a way of more or less precisely controlling this change in the size of objects, converging them into a single vanishing point. If the objects are close to the ground, this vanishing point will be precisely on the horizon line.
