This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Other topics and Adverse effects, Subject name: Pharmacology
[{'content': 'In case of hill journey, antimotion sickness drugs are best administered at: \nSelect and explain. \nA. Twelve hours before commencing journey, B. One hour before commencing journey, C. Immediately after commencing journey, D. At the first feeling of motion sickness', 'role': 'user'}, {'content': 'Answer: B \nExplanation: (Ref: KDT 6/e p641) Hyoscine is administered half to one hour before journey for prevention of motion sickness. It has no role once the vomiting stas.', 'role': 'assistant'}]