Answer:
b) epigenetics.
Explanation:
Epigenetics simply indicates the changes that do not alter the DNA sequence but influence the way genes are intercepted by the cells. Chemical compounds externally applied to single genes may modify their activity and these changes are known as epigenetic changes. Epigenetic variations persist as cells divide, and in some cases can be passed from one generation to another. The epigenome may also be influenced by environmental factors, for example, diet, exposure to contaminants, etc.
