In a sedimentary sequence of rocks, when the rocks are subjected to stress (pressure) horizontally, then it gives rise to the formation of a series of folds, which are characterized by distinct crests and troughs, which eventually forms long ridges and valleys. These ridges and valleys are oriented in such a way that they are directly perpendicular to the direction of the horizontal stress applied on these rocks.
These folds are very prominent in nature sometimes but most of the time, in an outcrop, they are covered by other rocks and sediments. These folds can be microscopic to macroscopic in scale.
These are some of the most important structures found in the sedimentary rock types.
<span>What happens to them would basically happen to everything only the earth's surface is more robust. The answer is c. they fold to create ridges and valleys perpendicular to the direction to which pressure is applied. This means that it takes the form based on the force that is applied to it which is in this case horizontal, meaning from sides instead of vertical which would be from up or down.</span>
Compared to early hominid ancestors, modern humans have jaws that are smaller and less rounded. I think this is what you're asking so I hope this helped you!