This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Unknown
[{'content': "Widmark's formula is used for measurement of blood levels of: \nSelect and explain. \nA. Benzodiazepines, B. Barbiturates, C. Alcohol, D. Tranquilizers", 'role': 'user'}, {'content': "Answer: C \nExplanation: Widmark's a = p.r.c., a= wt of alcohol in gms in body, p= body wt in kg, c= conc. of alcohol in blood in gm/kg, r = constant (0.6 for men, 0.5 for women).\nFor Urine, formula is- a = 3,4p.r.q, where q is the conc. of alcohol in urine in mg/kg.", 'role': 'assistant'}]