This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anatomy of skin, Subject name: Dental
Wave length of UV A2 rays is 
Select and explain. 
A. 200nm to 280nm, B. 280nm to 320nm, C. 320nm to 340nm, D. 340nm to 400nm
C: 320nm to 340nm
Answer: C: 320nm to 340nm 
Explanation: Ultraviolet light * Ultraviolet light (UV) is made up of: # Vacuum UVC (10-200 nm) # UVC (200-280 nm) # UVB (280-320 nm) # UVA (320-400 nm) divided into UVAII (320-340 nm) and UVAI (340-400 nm). Ref:- Review of Dermatology by Alikhan; pg num:-13