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Given below are statements related to different types of natural selection models.

A. Directional selection changes the average value of a trait.
B. Stabilizing selection increases variation in a trait.
C. Disruptive selection reduces variation in a trait.
D. Balancing selection maintains variation in a trait.

Select the correct option that represents the combinations of statements that are NOT true about natural selection.

Correct option is B

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Explanation:

• Statement A: Directional selection changes the average value of a trait. (True)
• Directional selection favors one extreme phenotype, leading to a shift in the population's average trait value over time.
• Statement B: Stabilizing selection increases variation in a trait. (False)
• Stabilizing selection actually reduces variation by favoring the intermediate phenotype and selecting against extreme variations.
• Statement C: Disruptive selection reduces variation in a trait. (False)
• Disruptive selection increases variation by favoring extreme phenotypes and selecting against intermediate ones.
• Statement D: Balancing selection maintains variation in a trait. (True)
• Balancing selection preserves genetic diversity in a population, preventing alleles from being lost.