Correct option is D
Pesticide residue analysis commonly employs chromatographic techniques such as:
• TLC (Thin Layer Chromatography): used for preliminary detection,
• GLC (Gas-Liquid Chromatography): effective for volatile pesticide compounds,
• HPLC (High-Performance Liquid Chromatography): widely used for non-volatile pesticides.
Hence, all three methods are instrumental in pesticide analysis.