Chemistry - Chemical Kinetics Question with Solution | TestHub

For a reversible reaction $\mathrm{R}\rightleftharpoons \mathrm{P}$, at constant temperature, both the forward and the backward reactions are first order elementary reaction with rate constant $k_f$ and $k_b$, respectively. At time zero, the concentration of $\mathbf{R}$ is $[\mathrm{R}{]}_0$ and the concentration of $\mathbf{P}$ is zero. At any given time $[\mathbf{R}]$ and $[\mathbf{P}]$ are the concentration of $\mathbf{R}$ and $\mathbf{P}$, respectively. If $k_b=4k_{\mathrm{f}}$, the correct graphical representation of the reaction is