Question

a horizontal line on a distance time graph represents
a zero velocity.
b constant negative velocity.
c constant positive velocity.
d constantly increasing velocity.

Explanation:

In a distance - time graph, the slope of the graph represents velocity. A horizontal line has a slope of 0. Since velocity is the rate of change of distance with respect to time (slope of distance - time graph), a horizontal line means that the distance is not changing with time. So, the velocity is zero.

Answer:

A. zero velocity