The salt $\text{NaClO}_3$ is employed as a non-selective weedkiller. When it is heated carefully: $4\text{NaClO}_3 \rightarrow \text{NaCl} + 3\text{NaClO}_4$. With stronger heating: $\text{NaClO}_4 \rightarrow \text{NaCl} + 2\text{O}_2$. The overall equation is $2\text{NaClO}_3 \rightarrow 2\text{NaCl} + 3\text{O}_2$. What do these equations indicate?
- A1, 2 and 3
- B1 and 2 only
- C2 and 3 only
- D1 only