PlEEEASE HELP! Which of the following statements about chemical equations is true?

Your

A: Changing the subscripts to balance an equation can only be done once.

B: Coefficients represent the relative amounts of the reactants and/or products, changing the subscripts to balance an equation can only be done once, and atoms are conserved when balancing chemical equations.

C: Coefficients represent the relative amounts of the reactants and/or products.

D: Coefficients represent the relative amounts of the reactants and/or products and atoms are conserved when balancing chemical equations.

E: Atoms are conserved when balancing chemical equations.