What contracts as it gets shorter?
layers of fat Epidermis Veins and arteries. Shortstop Labor Contracts the body's largest organ Bundles of fibers
A B C D E F G H
Muscles are bundles of fibers that can contract.
Bundles of fibers contraction occurs when bundles of fibers get shorter. 
What contracts as it gets shorter? (A) layers of fat (B) Epidermis (C) Veins and arteries. (D) Shortstop (E) Labor (F) Contracts (G) the body's largest organ (H) Bundles of fibers