Answer: The correct answer is-
B. Genotype
Enzymes are primarily proteins that help in regulating the various metabolic reactions that occur inside the living organisms (such as digestion of protrins, fats, carbohydrates).
Genotype can be described as the genetic makeup of a life form that contains essential instruction (in the form of DNA sequence) for the synthesis of different proteins.
DNA (deoxyribonucleic acid) undergoes transcription to form mRNA (messenger RNA), which ultimately forms particular protein via a process called translation.
Thus, enzymes present in an organism are basically regulated by the genotype of the organism.
