Question

when a bowling ball is at rest, it has inertia. what must happen in order for the bowling ball to start moving?
nothing, the bowling ball can move whenever it wants to
a force must act on the bowling ball

Explanation:

According to Newton's first law of motion (inertia), an object at rest stays at rest unless a net external force acts on it. A bowling ball at rest has inertia, so to make it move, a force (like a push or pull) must act on it. The first option is incorrect as objects don't move "whenever they want"—motion change requires force.

Answer:

a force must act on the bowling ball