Which of the following modulated signals are recovered up to scaling factor using envelope detector

$$\begin{gathered} If modulation index \left(m=\frac{A_m}{A_c}\right) is less than 1 , then we can say that signal recovering is better. \\ For option 1 \to m=\frac{30}{20}=1.5m>1 \\ For option 2 \to m=\frac{16}{20}=0.8m<1 \\ For option 3 \to signal contains only side bends, so message cannot be detected \end{gathered}$$