The IUPAC name of [Co (NH3)3 (NO2)3] is ?

The IUPAC name of [Co (NH3)3 (NO2)3] is ? (A) Trinitrotriammine cobalt (III) (B) Trinitrotriammine cobalt (II) (C) Trinitrotriammine cobalt (III) ion (D) Trinitrotriammine cobaltate (III)

(A) Trinitrotriammine cobalt (III)