This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Autoimmune Skin Disorders, Subject name: Skin
Toxic epidermal necrolysis (TEN) involves body surface area - 
Select and explain. 
A. < 10%, B. 10-20%, C. 20-30%, D. > 30%
D: > 30%
Answer: D: > 30% 
Explanation: Ans. is 'd' i.e., > 30%