Let's determine how a body can have acceleration when it has constant velocity in circular motion.
When a body has constant velocity, the acceleration is zero. This means a body travelling at constant velocity has no acceleration.
But when a body is in circular motion, it experiences a change in either the magnitude or a change in the velocity vector's direction.
Acceleration can be defined as a change in velocity, either in direction or magnitude.
Since there is a change in magnitude or the direction of vector in a circular motion, a body can have acceleration when it is at constant speed if the acceleration is kept perpendicular to the velocity.
ANSWER:
A body can have acceleration when it is at constant speed if the acceleration is kept perpendicular to the velocity.