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': 'In which of the following phases of clinical trials healthy normal human volunteers paicipate - \nSelect and explain. \nA. Phase I, B. Phase II, C. Phase III, D. Phase IV', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Phase I o Phase I involves normal human volunteers.", 'role': 'assistant'}]