How does cation exchange chromatography utilize the stationary resin to separate proteins based on charge?

• A. The resin binds negatively charged proteins, allowing positively charged proteins to elute first.
• B. The resin binds neutral proteins, allowing charged proteins to elute first.
• C. The resin binds all proteins equally, separating them based on size.
• D. The resin binds positively charged proteins, slowing their movement through the column.

Answer: (D)