Which of the following statements is false?

(P) Handpicking allows the good grains to be separated from the waste and impurities. (Q) A mixture of milk and water can be separated by filtration. (R) The method of separating seeds of paddy from its stalks is called threshing. (S) More of a substance can be dissolved in a solution by heating it. (T) Sieving is a method of separating substances that are of different sizes.