Moving Charge in a Magnetic Field question from NEET 1997 (AIPMT)

Answer: (c)

1. Near the poles the field lines are nearly vertical, so incoming particles move almost along $\vec{B}$ and are hardly deflected.
2. At the equator the field is horizontal, perpendicular to incoming particles, so they are bent away strongly ($r = \frac{mv}{qB}$).
3. Only particles with large momentum (energy) reach the equator.
4. So the answer is (c).