(1). sizing;
(2). Dehydration;
(3). kinetic energy;
(4). contracting;
(5). Energy;
(6). forces;
(7). destroying;
(8). embellishing;
Q: Fact 1: Muscles can only contract. Fact 2: Muscle size comes from lifting heavy weights. Given the two facts above, what comes from lifting heavy weights?
A:
(4).