This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Environment and health, Subject name: Social & Preventive Medicine
Day light factor in living room should be? 
Select and explain. 
A. 8%, B. 6%, C. 10%, D. 15%
A: 8%
Answer: A: 8% 
Explanation: park's textbook of preventive and social medicine 23rd edition. *daylight factor is the ratio of illumination at a given point to illumination at a point exposed simultaneously to the whole hemisphere of the sky excluding direct sunlight * it is recommended that in living room D.F. should be atleast 8%and in kichen about 10%.