Give the decreasing order of reactivity for the halogenation reaction of alkanes.

• A
  $F_{2} > Cl_{2} > Br_{2} > I_{2}$
• B
  $I_{2} > Br_{2} > Cl_{2} > F_{2}$
• C
  $Cl_{2} > F_{2} > Br_{2} > I_{2}$
• D
  $Br_{2} > Cl_{2} > F_{2} > I_{2}$