Which is a characteristic of centripetal acceleration?
it is directed outward from the center of a circle.
it is directed inward, toward the center of a circle.
it results in an object moving faster.
it results in an object moving slower.

It is directed inward, toward the center of a circle

Explanation:

I add a graph in order to explain all the following concepts.

The acceleration vector in a circle can be decomposed into two vectors.

A vector called centripetal acceleration which is perpendicular to the trajectory and its direction is inward the circle. This vector is responsible of the change in the direction from the velocity vector.

A second vector called tangential acceleration which is collinear with the velocity vector. This vector is responsible of the change in the magnitud from the velocity vector. If the object is accelerating, the tangential acceleration and the velocity vector will have the same sense. If the object is stopping, the tangential acceleration and the velocity vector will have opposite senses.

In the graph I drew the two cases. An object accelerating and an object stopping.