Assertion (A): In azide ion average oxidation number of \( \mathrm{Nis}-1 / 3 \). Reason (R): In...

Assertion (A): In azide ion average oxidation number of \( \mathrm{Nis}-1 / 3 \).
Reason (R): In azide ion two \( \mathrm{N} \) atoms have zero oxidation number and one has oxidation number \( -1 \).
(A) Both A and R are true and R is the correct explanation of A.br(B) Both A and R are true, but R is not the correct explanation of A.
(C) A is true, but R is false.
(D) A is false, but R is true.
(E) Both A and R are false.