For the precipitation group IV metal ions as their insoluble carbonates, a saturated `(NH_(4))_(2)CO_(3)` solution is added as a group reagent. But `Na_(2)CO_(3)` or `K_(2)CO_(3)` should not be used as the group reagent because
A. They will prevent the precipitation of group IV metal carbonates by forming soluble complex salts.
B. The presence or absence of `Na^(+)` or `K^(+)` in the original salt mixture can not be ascertained in group V tests.
C. These will make the solution highly alkaline due to hydrolysis and will prevent the precipitation of group IV metal ions.
D. They will precipitate out `Mg^(2+)` ion of group V(if present) along with group IV metal carbonates .
