During the free radical substitution of methane by chlorine, which stage has the smallest activation energy?
- A$\text{CH}_3\bullet + \text{Cl}_2 \rightarrow \text{CH}_3\text{Cl} + \text{Cl}\bullet$
- B$\text{Cl}\bullet + \text{Cl}\bullet \rightarrow \text{Cl}_2$
- C$\text{Cl}\bullet + \text{CH}_4 \rightarrow \text{CH}_3\bullet + \text{HCl}$
- D$\text{Cl}_2 \rightarrow \text{Cl}\bullet + \text{Cl}\bullet$