$A$ white precipitate was formed when $BaCl_{2}$ was added to the water extract of an inorganic salt. Further,a gas $X$ with a characteristic odour was released when the formed white precipitate was dissolved in dilute $HCl$. The anion present in the inorganic salt is ..... .

• A
  $I^{-}$
• B
  $SO_{3}^{2-}$
• C
  $S^{2-}$
• D
  $NO_{2}^{-}$