Over many generations, natural selection can lead to what outcome if the environment favors a particular trait?

• A. Random fixation of traits with no advantage
• B. Increase in frequency of the advantageous trait
• C. Decrease in population size
• D. Traits acquired during life are inherited

Answer: (B)

When the environment favors a particular trait, natural selection causes that trait to become more common in the population over many generations. Individuals with the advantageous trait tend to survive and reproduce more, so their genes are passed on more often. Over time, the frequency of the advantageous trait increases, and the population becomes better suited to its environment. The other ideas don’t fit as well: random fixation happens by chance rather than because the trait provides a consistent advantage; a decrease in population size isn’t a necessary outcome of selection for a trait; and traits acquired during life aren’t inherited—genetic information is passed to offspring, not acquired characteristics.