A gas X is passed through water to form a saturated solution. The aqueous solution on treatment with silver nitrate gives a white precipitate. The saturated aqueous solution also dissolves magnesium ribbon with evolution of a colourless gas Y. Identify X and Y.
A. `X` is `CO_(2)` and `Y` is `Cl_(2)`
B. `X` is `Cl_(2)` and `Y` is `CO`
C. `X` is `Cl_(2)` and `Y` is `H_(2)`
D. `X` is `H_(2)` and `Y` is `Cl_(2)`