Fossils are the preserved remains or traces of animals, plants, and other organisms from the remote past. Fossils of sea organisms that no longer exist are sometimes found in high mountain areas. How do scientists explain these discoveries?

• A.  A new climate caused an ocean to disappear.
• B.  The mountains were lifted from low, wet areas.
• C.  The fossils were carried there by flowing rivers.
• D.  The samples were left behind from volcanic eruptions.