Question

question: in polygenic traits, when the bell curve distribution of traits moves to one end of the curve because of a preference for best fit of that trait, whats this shift called? answer options: select one of four disruptive selection nonjunction selection stabilizing selection directional selection

Explanation:

To solve this, we analyze each option:

• Disruptive selection: Favors extreme traits at both ends, splitting the population. Not matching the shift to one end.
• Nonjunction selection: Not a recognized type of natural selection related to polygenic trait distribution.
• Stabilizing selection: Favors intermediate traits, reducing variation. Not a shift to one end.
• Directional selection: Occurs when natural selection favors one extreme of a polygenic trait, shifting the bell - curve distribution to one end. This matches the description in the question.

Answer:

D. Directional selection