Solid ReO3 is a material that is an extremely good conductor of electricity. It can be formed by the chemical reaction Re(s) 1 3Re₂O₇(s) → 7ReO₃(s). If 3 mol of Re and 3 mol of Re₂O₇ are placed in a reaction vessel and the reaction proceeds, 7 mol of ReO₃ are produced. Which of the following statements is the best reason that 7 mol of ReO₃ are produced during the chemical reaction?

a. According to the balanced chemical equation, 7 mol of ReO₃ will always be formed regardless of the starting amounts of the reactants.

b. Re is the limiting reactant.

c. Re₂O₇ is the limiting reactant.

d. Re₂O₇ is the excess reactant.

e. The 3 mol of Re completely reacts producing 7 mol of ReO₃.