Which description is an example of converting gravitational energy into kinetic energy?

When an object from a pause state begins to move the potential energy is changed into kinetic energy. One of the example is the yo-yo, it has stored energy due to its position. Once the yo-yo begins its fall the potential energy will change to kinetic energy and vice versa.

The adrenal gland

Explanation:

The adrenal gland which is located above the kidneys produces adrenaline, a stress  hormone that invokes a flight-or fight-response in the body. The body will experience increased heartbeats, tightened muscles, dilated pupils, and sweating. This gland is under the regulatory influence of the hypothalamus-pituitary-adrenal (HPA) axis.