Answer:
C. They have the same kinetic energy.
Step-by-step explanation:
Since Bobby slides down on a frictionless track, his final kinetic energy is equal to his initial potential energy.
Similarly, since Adam is on free-fall, his final kinetic energy will be equal to his initial potential energy.
Considering that they both started at the same height 4m above the ground, their initial potential energies, therefore final kinetic energies will be the same.