Affinity chromatography is a method of separating biochemical mixtures based on a highly specific interaction such as that between antigen and antibody, enzyme and substrate, or receptor and ligand. So, it is used for separation of immunoglobulins, cellular enzymes and mRNA based on interactions. Thus, option B is correct. Ion exchange chromatography is a process that allows the separation of ions and polar molecules based on their affinity to the ion exchanger. It can be used for almost any kind of charged molecule including large proteins, small nucleotides and amino acids. It is often used in protein purification, water analysis, and quality control. This technique is not used for separation of immunoglobulins, cellular enzymes and mRNA. Paper chromatography is an analytical method that is used to separate coloured chemicals or substances, especially pigments. This can also be used in secondary or primary colours in ink experiments.