(i) A powdered substance (A) on treatment with fusion mixture gives a green coloured compound (B). (ii) The solution of (B) in boiling water on acidification with dilute `H_(2)SO_(4)` gives a pink coloured compound `(C )`.
`(iii)` The aqueous solution of (A) on treatment with NaOH and `Br_(2)-` water gives a compound (D).
(iv) A solution of (D) in conc. `HNO_(3)` on treatment with lead peroxide at boiling temperature produced a compound (E) which was of the same coloure at that of (C).
(v) A solution of (A) on treatment with a solution of barium chloride gave a white precipitate of compound (F) Which was insoluble in conc. `HNO_(3)` and conc. HCl.
The oxidation state of central metal ions of (A), (B) and (C ) compounds are respectively `:`
A. `+II,+VI` and `+VII`
B. `+II,+VI` and `+VI`
C. `+II,+VII` and `+VII`
D. `+VI,+VII` and `+VII`
