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: Social & Preventive Medicine
[{'content': 'The Pearl index indicates the number of accidental pregnancies per- \nSelect and explain. \nA. 1000 population, B. 1 0 0 live bihs, C. 100 women in the age group of 15 to 44 years, D. 100 women years', 'role': 'user'}, {'content': "Answer: D \nExplanation: Ans. is 'd' i.e., 100 women years", 'role': 'assistant'}]