The correct answer is: B. The water before filtration is a mixture because the particles could be physically separated.
A mixture is composed of more than one individual substances that can be separated using different methods (depending on the type of mixture). Methods for the separation include filtration, evaporation, distillation and chromatography. The dirt stays behind in the filter paper (it becomes the residue) andthe water passes through the filter paper (it becomes the filtrate).
D. Artificial selection means that it doesn’t happen naturally, many dogs breeds exist because of artificial selection
