The Magnetic Field of Mars, Compared to That of Earth

The magnetic field of Mars, compared to that of Earth, is:

A) nonexistent anywhere on the planet.
B) very similar in strength and orientation, its north-south axis being almost along the planet's spin axis.
C) localized and very weak.
D) much stronger, but with its north-south axis lying in the equatorial plane, the north pole coinciding with the large volcano, Olympus Mons.