Which of the following is the best example of law of conservation of mass?
(A) 12 g of carbon combines with 32 g of oxygen to form 44 g of CO2.
(B) When 12 g of carbon is heated in a vacuum there is no change in mass.
(C) A sample of air increases in volume when heated at constant pressure but its mass remains unaltered.
(D) The weight of a piece of platinum is the same before and after heating in air.
