The correct statement regarding a distance vs. time graph is:
The graph should show distance on the vertical axis.
In a distance vs. time graph, distance is typically represented on the vertical (y) axis and time on the horizontal (x) axis. The other statements may not necessarily be true; for example, the graph can have curved segments, it does not need to have a horizontal segment unless the object is at rest, and it does not have to start at the origin if the object started at a distance greater than zero.