When Decomposed Chemically, 73

When decomposed chemically, 73.0 grams of a sample of HCl produce 71.0 g of Cl₂ and 2.0 g of H₂, while 34.0 g of a sample of H₂S produce 32.0 g of S and 2.0 g of H₂. This is an example of the Law:

A) of Conservation of Mass
B) of Multiple Proportions
C) of Definite Proportions
D) E = mc2
E) of Simple Whole Numbers