This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Non communicable diseases, Subject name: Social & Preventive Medicine
First disability census was done in the year? 
Select and explain. 
A. 1881, B. 1951, C. 1981, D. 2001
C: 1981
Answer: C: 1981 
Explanation: First disability census was taken in 1981