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: Pharmacology
[{'content': 'Methotrexate toxicity is treated by? \nSelect and explain. \nA. Folinic acid, B. Folic acid, C. Vitamin B 12, D. Folinic acid+Vitamin B 12', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Folinic acid Folinic acid rescue o Where it is desired to maximise the effect of methotrexate a potentially fatal dose is given and is followed 24 h later by a dose of folinic acid to terminate its action. o High concentrations of methotrexate are obtained and bone marrow cells recover better than the tumor cells and some degree of useful selectivity is achieved", 'role': 'assistant'}]