A rectangular loop of wire with width \(w\) and length \(L\) carries a steady current \(I\) in a uniform magnetic field of magnitude \(B\). The loop is free to rotate about a central axis parallel to its length \(L\). The angle \(\phi\) is defined as the angle between the plane of the loop and the magnetic field vector \(\vec{B}\). Which of the following graphs best represents the net magnetic torque \(\tau\) exerted on the loop as a function of \(\phi\) from \(\phi = 0\) to \(\phi = \pi \text{ rad}\)?