One reason researchers have long believed that Mars never enjoyed an extensive period of warm and wet climate is that much of the surface not covered by wind-borne dust appears to be composed of unweathered material If water flowed for an extended period, researchers reasoned, it should have altered and weathered the volcanic minerals, creating clays or other oxidized, hydrated phases (minerals that incorporate water molecules in their crystal structure).
It turns out. though, that the scientists were not looking closely enough. New high-resolution mapping data and close-up surface studies have revealed clays and other hydrated minerals in many regions The clay deposits are scattered all over, in ancient volcanic surfaces and heavily cratered highland regions, some of which have apparently been exposed by erosion only recently.
It can be inferred from the passage that the author would agree with which of the following statements regarding the reasoning discussed in the highlighted sentence?
A . It is based on an underestimation of the extent to which flowing water would alter volcanic materials on Mars
B . It provides the basis for an explanation of why water on Mars has been difficult to find until recently
C It correctly identifies a consequence of water flowing on the Martian surface.
C . It results in a new understanding of how water and volcanic materials interact on Mars.
D . It fails to take into account the impact of wind-borne dust on the Martian surface
Answer: C
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