An electron moving with a speed u along the positive x-axis at y=0 enters a region of uniform magnetic field `vecB=-B_0veck` which exists to the right of y-axis. The electron exits from the region after some time with the speed v at co-ordinate y, then
| A. |
v>u, y<0 |
| B. |
v=u, y>0 |
| C. |
v>u, y>0 |
| D. |
v=u, y<0 |
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