Two horses begin at rest. After a few seconds, horse A is traveling with a velocity of 10m/s west, while horse B is traveling with a velocity of 13m/s west. Which horse had greater acceleration?

A. Horse A because its change in velocity was greater than Horse B in the same time.
B. Horse B because its change in velocity was greater than Horse A in the same time.
C. Horse B because its change in velocity was the same as Horse A's, but it took less time.
D. Both horses had the same acceleration.