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
Which of the following is not an indicator for disability? 
Select and explain. 
A. HALE, B. DALY, C. Pearl index, D. Sullivan's index
C: Pearl index
Answer: C: Pearl index 
Explanation: 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.