This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Light, Subject name: Social & Preventive Medicine
Visible spectrum of light 
Select and explain. 
A. 370 - 740 nm, B. 740-1140 nm, C. 200 - 370 nm, D. 200 - 370 nm
A: 370 - 740 nm
Answer: A: 370 - 740 nm 
Explanation: Ans. is 'a' i.e., 370-740 nm o As perceived by the human eye; light consists of those wavelengths of electromagenatic radiation (approximately 400-700 mm) which are capable of eliciting retinal response.