Choose your answer from:
(I) animals
(II) mussels
(III) control boxes
(IV) heat energy
(V) energy barrier
(VI) a hydraulic system
(VII) activation energy
(VIII) kinetic energy

Fact 1: If an object is kicked then force is exerted on that object. Fact 2: Control boxes are objects. Given the two facts above, what has forced extered on it if kicked?
Answer:
(III)