The best option to model the motion of P waves (primary waves) is:
A. Pulling one end of a spring and releasing it.
P waves are longitudinal waves, meaning that the particles of the medium move back and forth in the same direction as the wave is traveling. When you pull one end of a spring and release it, you create compressions and rarefactions that mimic the motion of P waves. In contrast, option B (holding a ball up high and releasing it) primarily demonstrates gravitational potential energy and the motion of free fall, which is not representative of the longitudinal wave motion of P waves.