D. acceleration
Explanation:
When an object's speed and direction are known, its acceleration can also be determined.
Acceleration is defined as the change in velocity of a body in motion with time.
Most times, velocity and speed can be changed if the direction a body is traveling is known.
Acceleration = 
The S.I unit of acceleration is always expressed as m/s²
Learn more:
Acceleration brainly.com/question/3820012
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