The citric acid cycle intermediates are drained through ________ reactions

The question asks for the type of reactions that drain intermediates from the citric acid cycle.

• A. Amphiprotic: Describes a molecule that can act as both an acid and a base (proton donor and acceptor). This term is not related to metabolic pathways.
• B. Amphibolic: Describes a metabolic pathway that serves both catabolic (breakdown) and anabolic (synthesis) functions. The citric acid cycle itself is an amphibolic pathway, but this term doesn't specifically describe the draining of intermediates.
• C. Anaplerotic: Refers to reactions that replenish intermediates of a metabolic pathway, especially the citric acid cycle, when they are drawn off for biosynthesis.
• D. Cataplerotic: Refers to reactions that drain or remove intermediates from a metabolic pathway, such as the citric acid cycle, for use in other biosynthetic pathways.

Since the question specifically asks about intermediates being "drained," the term cataplerotic accurately describes these reactions.

The final answer is $\boxed{\text{D. Cataplerotic}}$.