In order to find the correct answer, let's analyze the correct formula that relates the speed, wavelength and period (or frequency) of a wavelength:
[tex]\begin{gathered} v=\lambda\cdot f\\ \\ f=\frac{1}{T}\\ \\ v=\frac{\lambda}{T} \end{gathered}[/tex]
Since it's more common to identify a wave by its frequency, the first formula is more used:
The speed is equal to the waveength tmultiplied by the frequency.
Correct option: B.
