Which of the following statements is/are correct regarding the electromagnetic spectrum?

I. In the EM spectrum, only a small fraction of wavelengths are visible to the human eye
II. The color seen by the human eye is determined by the specific wavelength
III. In the EM spectrum the majority of the range of wavelengths is visible to the human eye
IV. When photons are emitted from lasers, the wavelength of the photons is determined by the specific material used as a medium
a) I and II
b) II and IV
c) I, II, and IV
d) II only