The correct answer is option B.
The wavelength is related to frequency as c = νλ
where, ν is the frequency
λ is the wavelength
c is the velocity of the electromagnetic wave.
Now, wavelength is inversely proportional to the frequency
High-frequency ⇒ low wavelength
Now, from the diagram, highest frequency is in figure B. Here, in this figure, more number of waves occur in the given time., see figure B gas the highest frequency. So, it will have the shortest wavelength.
