Considering the elements $F,$ $Cl,$ $O,$ and $N,$ the correct order of their chemical reactivity in terms of oxidizing property is:
$(a)$ $F > Cl > O > N$
$(b)$ $F > O > Cl > N$
$(c)$ $Cl > F > O > N$
$(d)$ $O > F > N > Cl$

(B) The oxidizing character of elements increases from left to right across a period. Thus,the order of oxidizing property is $F > O > N$.
Furthermore,the oxidizing character of elements decreases down a group. Thus,we have $F > Cl$.
Comparing the electronegativity and electron affinity values,the oxidizing power of $O$ is greater than that of $Cl$ $(O > Cl)$.
Combining these trends,the correct order of oxidizing property is $F > O > Cl > N$.