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
Day light factor in living room should he? 
Select and explain. 
A. 8%, B. 6%, C. 10%, D. 15%
A: 8%
Answer: A: 8% 
Explanation: Ans. is 'a' i.e., 8%