Which of the following shows the conservation of mass during cellular respiration?
a) 3 CO2 + 3 H2O + energy → 3 C6H12O6 + 3 O2
b) 6 CO2 + 6 H2O + energy → C6H12O6 + 6 O2
c) C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + energy
d) 6 H2O + C6H12O6 → 6 O2 + energy