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': "Which of the following is not an indicator for disability? \nSelect and explain. \nA. HALE, B. DALY, C. Pearl index, D. Sullivan's index", 'role': 'user'}, {'content': "Answer: C \nExplanation: Pearl index is a measure of effectiveness of a contraceptive method. It is expressed as failure rate per 100 woman years and is not related to disability. Note: HALE - Health Adjusted Life Expectancy DALY - Disability Adjusted Life Years Ref: Park's Textbook of Preventive Medicine, 17th Edition, Pages 22, 351.", 'role': 'assistant'}]