The rate of change of displacement of a body with respect to its surrounding, is known

Answer: Option A

Displacement refers to the change in position of a body in a particular direction.

The rate of change of displacement with respect to time is defined as velocity.

Velocity is a vector quantity, meaning it has both magnitude and direction.

In contrast, speed is the rate of change of distance (not displacement) and is a scalar quantity.

Acceleration is the rate of change of velocity, not displacement.

Therefore, the correct term for the rate of change of displacement is Velocity.