This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Autonomic nervous system, Subject name: Pharmacology
[{'content': 'Drug which is used as pre-anaesthetic medication? \nSelect and explain. \nA. Atropine, B. Flavoxate, C. Glycopyrrolate, D. Hyoscine', 'role': 'user'}, {'content': "Answer: C \nExplanation: Glycopyrrolate is used as pre-anaesthetic medication, it is a quaernary amine which doesn't cross BBB and produce unnecessary CNS effects Ref: KDT 6th ed pg 109", 'role': 'assistant'}]