Which of the following best describes how proteins are separated in an affinity chromatography column?

• A. Proteins are separated based on their size as they pass through a gel matrix.
• B. Proteins are separated based on their charge differences in an electric field.
• C. Proteins are separated based on their specific binding to ligands attached to the stationary phase.
• D. Proteins are separated based on their solubility in the mobile phase.

Answer: (C)