Answer:

Step-by-step explanation:
Law of conservation of matter : It states that matter can neither be created nor be destroyed but it can only be transformed from one form to another form.
Balanced chemical reaction : It is defined as the reaction in which the number of atoms of individual elements present on reactant side must be equal to the product side.
A)

B)

C)
is correctly balanced as the number of atoms of hydrogen and oxygen are equal on the both side of the reaction.
D)