Please answer the following question by reasoning step-by-step.
What can a certain protein affect in meat?\nOptions:\n- (A) health\n- (B) piousness\n- (C) stamina\n- (D) retina\n- (E) toughness\n- (F) liveliness\n- (G) saltiness\n- (H) Energy

(E)
Cartilage is a tough tissue that contains a protein called collagen.

Collagen contributes to meat toughness.

A protein contributes to meat toughness.

.

Therefore, the answer is (E)