Which statement describes magnetic field lines at the north and south pole of a bar magnet?

a. field lines begin near the magnet's south pole and extend toward its north pole
b. field lines begin near both the magnet's north and south poles and meet in the middle
c. field lines begin near the center of the magnet and extend toward the north and south poles
d. field lines begin near the megnet's north pole and extend toward it's south pole