Which of the following happens when $\mathrm{NH}_4 \mathrm{OH}$ is added gradually to the solution containing 1 M $\mathrm{A}^{2+}$ and $1 \mathrm{M} \mathrm{B}^{3+}$ ions?

Given : $\mathrm{K}_{\text {sp }}\left[\mathrm{A}(\mathrm{OH})_2\right]=9 \times 10^{-10}$ and $\mathrm{K}_{\mathrm{sp}}\left[\mathrm{B}(\mathrm{OH})_3\right]=27 \times 10^{-18}$ at 298 K.

The molar solubility(s) of zirconium phosphate with molecular formula $\left(\mathrm{Zr}^{4+}\right)_3\left(\mathrm{PO}_4^{3-}\right)_4$ is given by relation :

For a sparingly soluble salt $$\mathrm{AB}_2$$, the equilibrium concentrations of $$\mathrm{A}^{2+}$$ ions and $$B^{-}$$ ions are $$1.2 \times 10^{-4} \mathrm{M}$$ and $$0.24 \times 10^{-3} \mathrm{M}$$, respectively. The solubility product of $$\mathrm{AB}_2$$ is :

Given below are two statements :

Statement (I) : A Buffer solution is the mixture of a salt and an acid or a base mixed in any particular quantities

Statement (II) : Blood is naturally occurring buffer solution whose $$\mathrm{pH}$$ is maintained by $$\mathrm{H}_2 \mathrm{CO}_3 / \mathrm{HCO}_3{ }^{\ominus}$$ concentrations.

In the light of the above statements, choose the correct answer from the options given below :