This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: general microbiology, Subject name: Microbiology
[{'content': 'Not a component of Gram stain - \nSelect and explain. \nA. Methylene blue, B. Ethanol, C. Iodine, D. Gentian violet', 'role': 'user'}, {'content': "Answer: A \nExplanation: GRAM STAINING 1) Primary staining with a pararosaniline dye such as crystal violet, Methyl violet,or Gentian violet 2) Application of a dilute solution of iodine . 3) Decolourisation with an inorganic solvent such as ethanol,acetone,or aniline . 4) Counterstaining with a dye of contrasting colour such as carbol fuchsin,safranine or neutral red . REF:Ananthanarayan & Panicker's Textbook of Microbiology 8th Edition pg no :15", 'role': 'assistant'}]