What is one of the facets of an organism's evolution?\nOptions:\n- (A) resistance\n- (B) fitness\n- (C) properties\n- (D) thirst\n- (E) movement\n- (F) swimming\n- (G) offspring\n- (H) recycling
Step-by-step reasoning process below:
(B)
Behaviors that improve fitness increase through natural selection.

Many organism behaviors have evolved through natural selection.

An organism's fitness is a result of evolution.

.

The final answer: (B)