Answer:
C. There is no genetic drift
Explanation:
A population is said to be in genetic equilibrium when the genetic variation of a population remains constant over many generations.
For a population to remain in genetic equilibrium it is necessary that external factors that disturb the equilibrium should not be present.
The external factors that are responsible for disturbing the genetic equilibrium are mutations, non-random mating, genetic drift and gene flow.
Genetic drift occurs when due to a chance event the allele frequency of a population either increases or decreases and this is usually common in small populations.
Thus, genetic drift should not occur so that the population can be in genetic equilibrium.
Absolute time is the answer
The correct terms to fill in the blanks would be contracts and dilates. In stressful situations, the sympathetic nervous system contracts the arteries of the circulatory system resulting to the dilation of the pupils of the eyes. Also, during these situations, the blood sugar levels are raised since the hormones for stress kick in to combat the stress which in turn raises the blood sugar.
A base substitution of G:C to A:T after two rounds of replication.