For a first-order reaction $$\mathrm{R}\rightarrow\mathrm{P}$$ at a given temperature, $$k$$ is the rate constant. For this reaction, at the given temperature, the concentrations of $$\mathrm{R}$$ and $$\mathrm{P}$$ at a time $$t$$ are $$[\mathrm{R}]$$ and $$[\mathrm{P}]$$, respectively. The correct graphical representation(s) for this reaction is(are)

A

B

C

D