The signal $m(t)$ as shown is applied both to a phase modulator (with $k_p$ as the phase constant) and a frequency modulator (with $k_f$ as the frequency constant) having the same carrier frequency.
The ratio $\frac{k_p}{k_f}$ (in $rad/Hz$) for the same maximum phase deviation is
- $8\pi$
- $4\pi$
- $2\pi$
- $\pi$