The study of changes in phenotype that are not related to changes in the dna and that may result from the interaction between the genotype and the environmenta. pleiogenetics
b. adaptation
c. epigenetics
d. menarche
e. homeoplasty

The correct answer is C. epigenetics

Explanation:

Epigenetics is the study of change in the phenotype that occurs not due to change in the DNA sequence but because of gene expression modification. So here we study the changes that occurred in phenotype, not in genotype.

DNA methylation, histone modification, etc can be responsible for the epigenetic changes in an organism. In DNA methylation, a methyl group or methyl cap is added to the DNA segment which prevents the expression of some genes.

The skin cell, brain cell, and muscle cells have the same DNA but due to epigenetic change(change in expression), they look different. So the correct answer is C. epigenetics.

the oxygenated blood then leaves the lungs through pulmonary veins, which return it to the left heart, completing the pulmonary cycle. this blood then enters the left atrium, which pumps it through the mitral valve into the left ventricle. from the left ventricle, the blood passes through the aortic valve to the aorta.

deoxygenated blood leaves through the right ventricle through the pulmonary artery. from the right atrium, the blood is pumped through the tricuspid valve (or right atrioventricular valve), into the right ventricle.

the statements that apply here about binary star system are

"have stars that might appear to wobble"

"often have one star that is brighter than other"

a binary star is a star system consisting of two stars revolving around their common barycenter. systems of two or more stars are called multiple star systems.