The answer is B I hope this helps luv
Answer:
The only such elements are the Noble Gases (He, Ne, Ar, Kr, Xe, Rn)
(that is helium, neon, argon, krypton, xenon and radon)
Term: Monoatomic
Explanation:
It is defined by their wavelength. Different colors have different wavelengths. For example, radio waves have a really long wavelength, whereas gamma-rays have a very short wavelength.
