How is natural selection best described?

Natural selection is a fundamental mechanism of evolution that describes how certain traits become more common in a population over generations. This process occurs when individuals within a species exhibit variations in their traits, and those individuals with traits that are better suited to their environment are more likely to survive and reproduce. This occurs because the advantageous traits increase the chances of survival against environmental challenges, predation, competition for resources, and other factors.

Over time, these favorable traits can become more prevalent in the gene pool, leading to gradual changes in the population. This process is often referred to as "survival of the fittest," where "fittest" refers to the most adapted to the current environment. Therefore, the description of natural selection as a process where individuals with advantageous traits tend to survive and reproduce accurately captures the essence of how natural selection operates in shaping species over time. This understanding is pivotal in the study of biology, as it explains the diversity of life and adaptation to changing environments.