An example of potential energy is 1. The air in an inflated balloon.
Potential energy is stored energy. The air in the inflated balloon has elastic potential energy because it is being stored in the ballon. If the mouth of the inflated balloon is released or if the balloon is popped, the potential energy in the balloon transforms into kinetic energy.
All of the other answer choices are examples of kinetic energy or energy in motion. The wrecking ball, boulder, and water are all moving which means that they all contain kinetic energy, not potential energy.