**Core Concept**
Amino acids and proteins can behave like zwitterions due to the presence of both a positively charged amino group and a negatively charged carboxyl group. This unique property allows them to be separated using a specific chromatographic technique.

**Why the Correct Answer is Right**
The technique that exploits the zwitterionic nature of amino acids and proteins is ion exchange chromatography. In this process, the positively charged amino group of the zwitterion is attracted to the negatively charged resin, allowing the separation of the amino acids or proteins based on their charge characteristics. The isoelectric point of the amino acid or protein is a critical factor in this separation, as it determines the pH at which the molecule has no net charge.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because size exclusion chromatography separates molecules based on their molecular size, not their charge properties.
**Option B:** This option is incorrect because affinity chromatography relies on the specific interaction between a molecule and a ligand, not the zwitterionic nature of amino acids and proteins.
**Option C:** This option is incorrect because reverse phase chromatography separates molecules based on their hydrophobic properties, not their charge properties.

**Clinical Pearl / High-Yield Fact**
Ion exchange chromatography is a crucial technique in biochemistry, used in various applications including protein purification, DNA sequencing, and clinical diagnostics. Understanding the zwitterionic nature of amino acids and proteins is essential for optimizing chromatographic separation techniques.

**Correct Answer:** C. Ion Exchange Chromatography