20.已知反應 2O_{3 (g)} → 3O_{2 (g)}，則下列對於反應速率的敘述何者正確？
(A)Rate = \(-\frac{1}{3} \frac{\Delta[\text{O}_3]}{\Delta t} = -\frac{1}{2} \frac{\Delta[\text{O}_2]}{\Delta t}\)
(B)Rate = \(-\frac{1}{2} \frac{\Delta[\text{O}_3]}{\Delta t} = \frac{1}{3} \frac{\Delta[\text{O}_2]}{\Delta t}\)
(C)Rate = \( \frac{1}{2} \frac{\Delta[\text{O}_3]}{\Delta t} = \frac{1}{3} \frac{\Delta[\text{O}_2]}{\Delta t} \)
(D)Rate \( = -\frac{\Delta[\text{O}_3]}{\Delta t} = \frac{\Delta[\text{O}_2]}{\Delta t} \)