**Core Concept**
The process described involves the transfer of functional groups between amino acids and keto acids, a fundamental aspect of amino acid metabolism. This reaction is crucial for the synthesis and degradation of amino acids and is mediated by specific enzymes.

**Why the Correct Answer is Right**
This process is known as transamination, where the amino group (-NH2) of an amino acid is transferred to a keto acid, resulting in the formation of a new amino acid and the corresponding keto acid. This reaction is facilitated by transaminase enzymes, which catalyze the transfer of the amino group between amino acids and keto acids. The reaction involves the conversion of the keto group (-CO-) of the keto acid to the amino group, and vice versa.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not describe the transfer of functional groups between amino acids and keto acids.
**Option B:** This option is incorrect because it describes a different reaction, where the entire amino acid molecule is transferred, rather than just the amino group.
**Option C:** This option is incorrect because it refers to a different type of reaction, where the carboxyl group (-COOH) is transferred, rather than the amino group.

**Clinical Pearl / High-Yield Fact**
Transamination reactions are essential for the synthesis and degradation of amino acids, and are involved in the metabolism of many important amino acids, including glutamate, aspartate, and alanine.

**Correct Answer:** C. Transamination.