The overriding idea in any piece of fiction is known as its?

The overriding idea in any piece of fiction is known as it's plot

To form soil, the two processes which must occur are erosion and weathering, so the correct answer is "soil formation is a continuous presses, but also one which takes a long time, it can sometimes take more than five hundred years for 1cm of soil to form.

The answer is focused on because it boils down to the fact means to focus on.