A distance-time graph shows a horizontal line at a distance of 3 km.
Explain the motion of the object.

Because the earth is not round ,but it may seem round when viewed from ,our planet but true some points earth is not round was an oblate spheroid -a square that it squashed as globe however is not even a perfect oblate spheroid.in fact isaac newton's first proposed that earth was not perfectly round but it was an oblate spheroid instead.that mean a square that is squashed as its poles and swollen at the

C) reflection (i also looked up the other choices just to make sure)

They formed the oceans.  as they melted water was formed and the water made the oceans