What Is the Great Red Spot on Jupiter

Multiple Choice

What is the Great Red Spot on Jupiter?

A) the summit of a large mountain that rises above the upper cloud level
B) a region over the south pole of Jupiter where ammonia compounds that absorb blue light have condensed in the colder atmosphere
C) an area where charged particles from the satellite Io collide with Jupiter's cloud tops
D) a large, long-lived anticyclonic storm that is maintained by the differential rotation of Jupiter's atmosphere