Questions: Natural selection causes adaptations to become more common in a population over generations. can be random if the population is very small.

The correct statement is: "Natural selection causes adaptations to become more common in a population over generations."

Explanation for each option:

1. Natural selection can help individuals become better adapted to the environment within their lifetime.

   • This is incorrect. Natural selection does not act on individuals within their lifetime. Instead, it acts on the variation present in a population, favoring those individuals whose traits are better suited to the environment, leading to those traits becoming more common in future generations.

2. Natural selection causes adaptations to become more common in a population over generations.

   • This is correct. Natural selection is the process by which traits that enhance survival and reproduction become more common in successive generations of a population. It acts on heritable traits, leading to evolutionary changes over time.

3. Natural selection can be random if the population is very small.

   • This is incorrect. Natural selection is a non-random process where certain traits become more common because they confer a survival or reproductive advantage. However, in small populations, genetic drift (a random process) can have a significant impact, but this is separate from natural selection.

4. Natural selection can favor very strong individuals even if they don't leave the most offspring.

   • This is incorrect. Natural selection favors traits that increase an individual's reproductive success. If strong individuals do not leave more offspring, their traits are less likely to be passed on and become more common in the population.

In summary, natural selection is a process that increases the frequency of advantageous traits in a population over generations, leading to adaptation.