Which of the following is an example of a beneficial mutation?

A. a mutation causing uncontrolled cell division in human tissue cells
B. a mutation inhibiting human immunodeficiency virus from entering the host cell
C. a mutation resulting in partial or complete loss of chlorophyll pigments in plants
D. a mutation resulting in a squirrel being born without ovaries

Answer: B. a mutation inhibiting human immunodeficiency virus from entering the host cell

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