The correct answers are:
- Erosion can be harmful to the environment; bigger erosion in a shorter time span can be very destructive to the environment because whole layers of soil will be moved away and the landscape and the features of the environment will be changed.
- Erosion is caused by human activities; people have a big impact on the erosion, mainly by destroying the vegetation which is essential for prevention of this process.
- Erosion is caused by the wind, water, and gravity; these three are the natural factors that are causing the erosion, and that manage to move the soil away from a particular place.
- The process of erosion moves soil; the process of erosion in its essence means exactly that, moving of soil, and while this is bad for the place from where the soil is moved away, it can be good for the place where the material will be deposited later on.
