A scientist is studying an infectious agent in a lab. Which observation best illustrates the importance of the theory of evolution in the field of medicine?

Evolution explains how populations change when some individuals have traits that help them survive and reproduce. If a mutation lets organisms in Petri dish D survive medication, those organisms may multiply while others die, making the infectious agent harder to treat. This is why the observation about medication resistance is important in medicine; cell size, gene count, or toxin production alone do not show this process.

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