Final answer:
Answering the question of "why" something happens in science is associated with the goal of explanation, particularly in the hypothesis stage of scientific inquiry, aiming to understand natural phenomena.
Step-by-step explanation:
The question of "why" something happens is most closely associated with the goal of explanation in science. This correlates to the hypothesis-building stage, where a proposed explanation that can be tested is formed. It is this explanatory aspect that further distinguishes a theory or a law in science, which is an experimentally supported hypothesis that has achieved wide acceptance to guide future observations and hypotheses.
Physicists, for instance, develop hypotheses and ultimately theories to explain phenomena within the natural world, aiming to understand the composition, structure, and changes that matter undergoes in the universe. The empirical approach to scientific inquiry relies on forming hypotheses to explain and predict phenomena, which then must be tested by experimentation.