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
Percentage of para–para isomer in it DDT is – 
Select and explain. 
A. 20–30%, B. 40–50%, C. 60–70%, D. 70–80%
D: 70–80%
Answer: D: 70–80% 
Explanation: None