What evidence supports the hypothesis for a vast, deep ocean which once occupied what is now the northern plains of Mars?
A) many of the largest flood channels appear to have drained into the northern plains
B) geographic features that look like ancient shorelines
C) that the rock along the proposed shoreline is sedimentary rather than volcanic
D) all of these are evidence

Question

Quizplus · Accepted Answer

All of these pieces of evidence support the hypothesis for a vast, deep ocean which once occupied what is now the northern plains of Mars. The fact that many of the largest flood channels appear to have drained into this region suggests the presence of a large body of water, while geographic features that look like ancient shorelines and sedimentary rock along the proposed shoreline provide further support for the idea.

What Evidence Supports the Hypothesis for a Vast, Deep Ocean