The human eye can view electromagnetic radiation of wavelengths from 400 nano-meter to

(A) 500 nano-meter
(B) 600 nano-meter
(C) 700 nano-meter
(D) 800 nano-meter

The answer is: (C) 700 nano-meter
The human eye can view electromagnetic radiation of wavelengths from 400 nano-meter to 700 nano-meter.