Which of the following graphs are correct for a zero order reaction ?

For a zero order reaction, $$\begin{gathered} \left[\mathrm{R}\right]=\left(-\mathrm{k}\right)\mathrm{t}+{\left[\mathrm{R}\right]}_{\mathrm{o}} .....\left(\mathrm{i}\right) \\ \uparrow \uparrow \uparrow \\ \mathrm{y}=\mathrm{m}\times \mathrm{x}\times \mathrm{c} \end{gathered}$$

 

On comparing with equation of straight line 
                        y = [R] concentration
                        x = t time
          Slope (m) = - k rate constant
       Intercept (c) =  [R ]_o initial concentration
On rearranging Eq. (i) 
$\begin{array}{l}\frac{\left[\mathrm{R}\right]-[\mathrm{R}{]}_0}{\mathrm{t}}=-\mathrm{k}\\ \frac{\left[\mathrm{R}\right]-[\mathrm{R}{]}_0}{\mathrm{t}}=-{\mathrm{kt}}^0\\ \text{ Rate }\propto {\mathrm{t}}^0\end{array}$