The correct response is: It shows that no atoms have been gained or lost during the reaction.
This statement reflects the Law of Conservation of Mass, which states that in a chemical reaction, the total mass of the reactants must equal the total mass of the products. In the balanced equation provided, the number of atoms of each element on the reactant side (2 Fe₂O₃ + 3 C) equals the number of atoms of each element on the product side (4 Fe + 3 CO₂), demonstrating that mass is conserved and no atoms are lost or gained during the reaction.