Which major chromatographic mode is correctly paired with its primary separation principle?

Which major chromatographic mode is correctly paired with its primary separation principle?

• A. Ion-exchange chromatography — separation based on charge interactions with a resin.
• B. Gas chromatography — separation by adsorption onto a solid stationary phase.
• C. Size-exclusion chromatography — separation by chemical affinity to ligands.
• D. Thin-layer chromatography — separation primarily by partitioning into a liquid stationary phase.

Answer: (A)