Question: In a balanced chemical equation?
A) atoms are conserved
B)molecules are conserved
C) moles are conserved
D) reactant and product are conserved  Edit

Answer: Balancing a chemical equation refers to establishing the mathematical relationship between the quantity of reactants and products. The quantities are expressed as grams or moles. The same number of atoms (or moles of atoms) of a given type must appear on each side of the equation.
According to the Dalton’s third postulate that atoms are neither created, destroyed, nor changed from one kind to another during a chemical process. And law of conservation of mass is obeyed.

So with respect to your answer, A) atoms are conserved  Edit