A parallel-plate capacitor with plate area \(A\) and initial plate separation \(x_0\) is connected in series with an ideal battery of potential difference \(\mathcal{E}\) and a resistor of resistance \(R\). The system has been connected for a long time so that the capacitor is fully charged. Beginning at time \(t = 0\), an external mechanism pulls one plate away from the other at a constant speed \(v\), increasing the plate separation according to \(x(t) = x_0 + vt\). Which of the following best describes the shape of the graph of the current \(I(t)\) through the resistor as a function of time \(t\) for \(t \ge 0\)?