In amplitude modulation, the sinusoidal carrier frequency used is denoted by $\omega_{\rm{c}}$ and the signal frequency is denoted by ${\omega }_{\mathrm{m}}$. The bandwidth $\left(\Delta {\omega }_{\mathrm{m}}\right)$ of the signal is such that $\Delta {\omega }_{\mathrm{m}}\ll {\omega }_{\mathrm{c}}$. Which of the following frequencies is not contained in the modulated wave?

This question has Statement$-1$ and statement$-2$. Of the four choices given after the statements, choose the one that best describes the two statements.

Statement$-1$: Skywave signals are used for long-distance radio communication. These signals are in general, less stable than ground wave signals.

Statement$-2$: The state of the ionosphere varies from hour to hour, day to day and season to season.