In a uniformly charged sphere of total charge $Q$ and radius $R$, the electric field $E$ is plotted as a function of distance $r$ from the centre. The graph which would correspond to the above will be:

Inside a uniformly charged non-conducting sphere ($r<R$):$E_{\text{in}}=\frac{1}{4\pi {ϵ}_0}\frac{Qr}{R^3}\propto r$ Outside the sphere ($r>R$):$E_{\text{out}}=\frac{1}{4\pi {ϵ}_0}\frac{Q}{r^2}\propto \frac{1}{r^2}$ At $r=R$, $E=\frac{1}{4\pi {ϵ}_0}\frac{Q}{R^2}$.The graph starts from zero at the centre, increases linearly up to $R$, and then decreases following an inverse square law. This matches Graph (3) in standard textbook representations.