In the context of gluconeogenesis, what is the significance of biotin's role in pyruvate carboxylase?

• A. It inhibits the conversion of pyruvate to acetyl-CoA.
• B. It is not involved in gluconeogenesis.
• C. It acts as a competitive inhibitor of pyruvate carboxylase.
• D. It facilitates the conversion of pyruvate to oxaloacetate, a key step in gluconeogenesis.

Answer: (D)