Answer: Option (A) is the correct answer.
Explanation:
It is know that wavelength is inversely proportional to the frequency.
Mathematically,

where
= wavelength
v = frequency
c = speed of light
Therefore, when there will be increase in wavelength then there will be decrease in frequency and vice-versa.
Hence, we can conclude that the statement a low frequency wave has a long wavelength best describes the wavelengths of a certain frequency.