Starting Outside the Region with the Magnetic Field,a Single Square $\vec { B }$

Multiple Choice

Starting outside the region with the magnetic field,a single square coil of wire enters,moves across,and then leaves the region with a uniform magnetic field $\vec { B }$ perpendicular to the page so that the graph shown below represents the induced emf.The loop moves at constant velocity $\overrightarrow { \mathbf { v } }$ .As seen from above,a counterclockwise emf is regarded as positive.In which direction did the loop move over the plane of the page?

A) The loop moved from bottom to top.
B) The loop moved from top to bottom.
C) The loop moved from left to right.
D) The loop moved from right to left.
E) All of these directions of motion will produce the graph of emf vs t.