The graph shows how the flux through a loop changes with time. Which graph shows the emf induced in the loop?

Fig. 1: A graph of magnetic flux in milliweber against time in seconds. The flux rises in a straight line from 0 at 0 s to 4 mWb at 2 s, stays at 4 mWb until 4 s, and then falls in a straight line to 0 at 5 s.