The law of conservation of mass states a) matter can be created and destroyed but does not change forms

b) the mass of all substances present before a chemical change equals the mass of all the substances remaining after the change

c) in a chemical reaction, efforts should be made to preserve rare elements without changing them.

d) in a chemical reaction, the final mass of the products is always greater than the starting mass of the reactants.

I think your answer would be B.

explanation: pretty sure this is correct if not i am so sorry and good luck! <3

You would be correct, boiling water does disinfect contamination.    the property of disinfecting means to kill  germs, bacteria and other pathogens or contamination  that might cause an infection or cause a person to become sickly. a couple methods of disinfecting are using soap, other cleaning supplies or by simply "boiling" the contaminate.  the reason why boiling water disinfects certain attributes is because some cells cannot survive the heat and pressure.