The frequency of the electromagnetic wave is same as that of oscillating charged particle about its equilibrium position, which is 10⁹ Hz.

 Here, 

$$\begin{gathered} v ={10}^9 \mathrm{Hz}, \\ \Rightarrow \lambda =\frac{c}{v}=\frac{3\times {10}^8}{{10}^9}=0.3 \mathrm{m} \end{gathered}$$ 

This wavelength of radiation $\left(0.3 \mathrm{m}\right)$ or frequency of radiation $\left({10}^9 \mathrm{Hz}\right)$ falls in the region of radio waves.

Hence all options are correct.