If life exists where there are bodies of water and land to farm on how does geography influence stratification?

If there are bodies of water and land to cultivate nearby then that is a good situation for agriculture to take place so that there is where to plant and also a source of water to keep the plants alive and growing. Where human beings find such a geographic situation, say like along the Nile River then a class of small farmers can develop and this is a social stratum. 

Answer (d) may increase or decrease porosity through dissolution or deposition;