Amplitude modulated signals contain frequencies:

($\omega_c = \text{ carrier wave frequencies } , \omega_m = \text{ modulating signal frequencies}$)

(A) $\omega_c$

(B) 2$\omega_c$

(C) $\omega_c + \omega_m$

(D)  $\omega_c - \omega_m$

Choose the correct answer from the options given below:

(A) , (C) and (D) Only

 The modulation wave has namely three frequencies. 

$(\omega_c - \omega_m) , \omega_c \text{ and }(\omega_c + \omega_m)$ . 

$\omega_c$ is the carrier wave frequency, $\omega_c + \omega_m$ is the upper side band frequency and $\omega_c - \omega_m$ is lower side band frequency.