Fact 1: Shivering occurs when many muscles contract a little bit all at once. Fact 2: Shivering heats the body. Given the two facts above, what does muscles contracting a little bit all at once do?

Pick your answer from:
(A). biceps;
(B). cause death;
(C). respiration;
(D). staying warm;
(E). rapid expansion;
(F). movement;
(G). heat the body;
(H). to move people;
Answer:
(G).