Answer:
A. a hammer dropped off a roof accelerates as it falls.
Step-by-step explanation:
The example that illustrates gravitational potential energy transforming into kinetic energy is a hammer dropped off a roof accelerating as it falls.
Gravitational potential energy is the energy due to the position of a body.
A hammer held up at roof level has a measure of gravitational potential energy.
As it drops and begins to accelerate, the energy is converted to kinetic energy. Kinetic energy is the energy due to the motion of a body.
The acceleration due to gravity causes the body to move.
So, the gravitational potential energy is converted to kinetic energy.