In this exercise we have to use our knowledge of biology to identify the true alternative, so we have:
The correct anwser is Natural selection produces animals fit for their environment or letter B.
How does the process of natural selection happen?
Natural selection acts on the phenotype, or observable characteristics of an organism, in such a way that individuals with favorable phenotypes are more likely to survive and reproduce than those with less favorable phenotypes.
So we can say that the main reason for natural selection is due to the competition of the animal to survive in a certain environment.
See more about natural selection at brainly.com/question/1131859