A) when the soil is stripped by wind or water.. when this happens the soil can be rid of it's nutrients and fertility.. The other options are actually kind of helpful, when the bedrock is damaged by animals (unless you've already set up and everything) it actually helps to till the soil, the water will help to moisten it and make it better or providing life (depending upon the amount of water tht is) and burrowing animals can consist of worms to groundhogs.. depending upon the plans for said soil, It could be helpful with the worms, but the plans could be altered by the groundhog.. but referring to the original question, It definitely loses it's value when it's stripped by wind and water.
