Look at the following chemical equation.

4Al + 3O2 → 2Al2O3

What is true about this chemical equation?
A
It is balanced because the mass of the reactants is equal to the mass of the products.

B
It is balanced because the number of reactants is equal to the number of products.

C
It is unbalanced because the mass of the reactants is greater than the mass of the products.

D
It is unbalanced because the number of reactants is greater than the number of products.