This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Drugs, Subject name: Skin
[{'content': "Whitfield's ointment consists of - \nSelect and explain. \nA. 3% salicylic acid + 6% benzoic acid, B. 3% benzoic acid + 6% salicylic acid, C. 2% salicylic acid + 4% benzoic acid, D. 2% benzoic acid + 4% salicylic acid", 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., 3% salicylic acid + 6% benzoic acid Whitfield's Ointmento Whitfield's ointment is salicylic acid and benzoic acid in a suitable base, such as lanolin or vaseline,o The original ointment contains 3% salicylic acid and 6% benzoic acid, but other ratios are also used,o It is used for the treatment of fungal infections, such as athlete's foot. Its effectiveness is unclear,o It can have a slight burning effect that goes away after a few minutes,o It is named for Arthur Whitfield (1868-1947), a British dermatologist.", 'role': 'assistant'}]