Two particles of identical mass \(m\) travel in the \(xy\)-plane with speed \(v_0\) at symmetric angles \(\theta\) relative to the \(+x\)-axis, having velocity vectors \(\vec{v}_1 = v_0\cos\theta\,\hat{i} + v_0\sin\theta\,\hat{j}\) and \(\vec{v}_2 = v_0\cos\theta\,\hat{i} - v_0\sin\theta\,\hat{j}\), where \(0 \le \theta \le \dfrac{\pi}{2}\). The particles collide and stick together to form a single combined object of mass \(2m\). Which of the following graphs best represents the fraction of the initial translational kinetic energy dissipated during the collision, \(\dfrac{\Delta K}{K_i}\), as a function of \(\theta\)?