Answer:
Most fish use gills for gas exchange instead of lungs.
Explanation:
According to the research, the correct option is A, population genetics is the study of how allele frequencies in a population change over time.
<h3>What is population genetics?</h3>
It studies the origin, amount and distribution of genetic variability present in populations.
It explains the variation between individuals, as well as the dynamics of alleles and genotypes within and between populations.
Therefore, we can conclude that according to the research, the correct option is A, population genetics is the study of how allele frequencies in a population change over time.
Learn more about population genetics here: brainly.com/question/13049509
#SPJ1
A. True ! Energy can be lost, but not created nor destroyed.
