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
In a village of 1 lakh population, among 2,000 exposed to smoking, 20 developed lung cancer and among 8,000 unexposed people, 8 developed lung cancer. What is attributable risk - 
Select and explain. 
A. 10%, B. 50%, C. 90%, D. 100%
C: 90%
Answer: C: 90% 
Explanation: Ans. is 'c' i.e., 90%