The Great Dark Spot on Neptune, Photographed by Voyager 2

Multiple Choice

The Great Dark Spot on Neptune, photographed by Voyager 2 during its flyby of the planet, is considered to be a

A) region of upwelling gas in Neptune's atmosphere, above a hot spot on its surface, possibly a volcano.
B) storm system probably centuries old, like Jupiter's Great Red Spot.
C) volcanic caldera.
D) relatively short-lived storm system.