The main point is the opening paragraph.
People had hoped to find methane on Mars, but could not.
Para 2: Gives the reasons for their initial hopes. That they thought Methane based life was possible
Para 3: Goes on to explain their methodology for trying to find that Methane.
Former GMAT Pill student, now on staff. Used GMATPILL OG 12 and nothing else: 770 (48,48) & 6.0
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