Which equation represents the initiation reaction when methane reacts with chlorine in the presence of ultraviolet light?

A.     ${\text{C}}{{\text{H}}_{\text{4}}} \to {\text{C}}{{\text{H}}_{\text{3}}} \bullet  + {\text{H}} \bullet$

B.     ${\text{C}}{{\text{l}}_2} \to {\text{2Cl}} \bullet$

C.     ${\text{C}}{{\text{l}}_2} \to {\text{C}}{{\text{l}}^ + } + {\text{C}}{{\text{l}}^ - }$

D.     ${\text{C}}{{\text{H}}_3} \bullet  + {\text{C}}{{\text{l}}_2} \to {\text{C}}{{\text{H}}_3}{\text{Cl}} + {\text{Cl}} \bullet$

B