Answer:
The beam of electrons would be flattened into a oval that is long in the x-axis and short in the y-axis.
Explanation:
A beam of moving electrons enters the quadrupole, with velocity parallel to the charged rods. When the beam enters the device, its cross-sectional profile is circular. On the other side, the beam of electrons would be flattened into a oval that is long in the x-axis and short in the y-axis.
The directions is shown in figure.