Plz help, its for my CFE in physical science honors.

Glen is explaining the relationship between the wavelength and frequency of electromagnetic radiation to his friend, Harold. Which of the following would be a correct explanation of this relationship?

A. All electromagnetic waves have the same frequency, but different wavelengths
B. If a wave has a long wavelength, it will have a low frequency.
C. If a wave has a low frequency, it will have an equally low wavelength.
D. The frequency of a wave is not related to its wavelength.