The Rovers Named Spirit and Opportunity That Recently Explored the Surface

Multiple Choice

The rovers named Spirit and Opportunity that recently explored the surface of Mars discovered

A) tiny streams of flowing water too small to be detected by orbiting satellites.
B) minerals that must have formed in an environment rich in liquid water.
C) dust storms that rapidly erode the surfaces of most geological formations.
D) the northern polar ice cap is made primarily of frozen water.
E) the presence of methane that arises from biological life.