What does evolution mean? A A rapid change in the environment that causes a reduced gene pool.
B Selectively acquiring useful genes.
C A gradual change in characteristics over time.
D Changing characteristics to suit the environment over a short period of time.

Explanation:

Evolution may be defined as any net directional change or any cumulative change in the characteristics of organisms or populations over many generations—in other words, descent with modification… It explicitly includes the origin as well as the spread of alleles, variants, trait values, or character states

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