HPLC technique families: Which set correctly lists the major high-performance liquid chromatography modes commonly used in laboratories?

Introduction / Context:
HPLC is not one technique but a platform supporting multiple separation mechanisms. Knowing the main HPLC modes guides analysts in matching chemistry to the problem: polarity differences, charge, or size.

Given Data / Assumptions:

• Partition (liquid/liquid, now typically liquid–stationary bonded phase) separates by differential partitioning.
• Adsorption (liquid/solid, e.g., normal-phase on silica) separates by surface interactions.
• Ion-exchange separates by electrostatic interactions; size exclusion (gel permeation) separates by hydrodynamic volume.

Concept / Approach:
HPLC modes correspond to analyte–stationary phase interaction types. Reversed-phase (a partition variant) dominates for small molecules, ion-exchange suits ionic biomolecules, and size exclusion is preferred for polymers and proteins where minimal interaction is desired.

Step-by-Step Solution:
Enumerate common modes: partition, adsorption, ion-exchange, and size-exclusion.Confirm each option names a legitimate HPLC mode.Choose the comprehensive option listing all.

Verification / Alternative check:
Method compendia (e.g., pharmacopeias) and HPLC vendor manuals organize columns and applications by precisely these modes.

Why Other Options Are Wrong:

• Options (a), (b), (c) are subsets; none alone is exhaustive.

Common Pitfalls:
Equating reversed-phase only with HPLC; while dominant, it is one of several modes.

Final Answer:
all of the above