During catabolism of amino acids, the release of amino group is known as

The correct option is deamination.

Amino acids are the building blocks of proteins, and each amino acid contains an amino group (-NH₂) and a carboxyl group (-COOH). During the metabolism of proteins, particularly when amino acids are broken down (catabolized) for energy or converted into other molecules, the body must handle the nitrogen-containing amino group.

The process of removing this amino group from an amino acid molecule is chemically termed deamination.
When the amino group is removed, it is typically released in the form of ammonia (NH₃), which is subsequently converted into urea in mammals (via the urea cycle) and excreted from the body. The remaining carbon skeleton of the amino acid is then oxidized to generate energy or used to synthesize glucose or lipids.

Let us briefly look at why the other options are incorrect:
- Hydrolysis is a chemical reaction in which water is used to break down chemical bonds (for example, breaking peptide bonds between amino acids in a protein).
- Hydration is the chemical addition of water to a molecule without breaking it down.
- Ammunition is a non-biological term referring to military supplies like bullets or shells, and is completely unrelated to biochemistry.