What is meant by a "source of error"?

1. any body of surface water in which water is stored is a(n) aquifer reservoir channel floodplain 2.which of the following is a source of groundwater replenishment? seepage into springs infiltration from the surface evaporation all of the above 3. watersheds are bounded by points of high elevation called drainage basins. true false 4.non-native species can harm watershed environments by competing with native species for food. true false