Answer:
Option (D).
Explanation:
Metabolic pathways are the series of various chemical reactions that link the other reaction of the cells with each other. The metabolites are generated during the metabolic reactions.
These pathways increases the energy of efficiency transfer and a single enzyme catalyzes a specific reaction. Most metabolic pathways are not reversible or irreversible under the physiological condition of the cell.
Thus, the correct answer is option (d).