Assign $A$,$B$,$C$,$D$ from the given type of reaction.
$K_2[Cd(CN)_4] + H_2S \longrightarrow CdS \downarrow + 2KCN + 2HCN$

The solubility of $PbI_2$ at $25\,^{\circ}C$ is $0.7\, g\, L^{-1}$. The solubility product of $PbI_2$ at this temperature is (molar mass of $PbI_2 = 461.2\, g\, mol^{-1}$)

The solubility product of $PbS$ is $3.4 \times 10^{-28}$. If $[Pb^{2+}] = 1 \times 10^{-2} \ mol/L$,what concentration of $[S^{2-}]$ is required to precipitate $PbS$?

The best explanation for the solubility of $MnS$ in dil. $HCl$ is that

Solubility products $(K_{sp})$ of the salts of types $MX, MX_2$ and $M_3X$ at temperature $T$ are $4.0 \times 10^{-8}, 3.2 \times 10^{-14}$ and $2.7 \times 10^{-15}$ respectively. Solubilities (in $mol \text{ dm}^{-3}$) of the salts at temperature $T$ are in the order:

What mass of $AgI$ will dissolve in $1.0 \ L$ of its saturated solution? [Given $: K_{sp}(AgI) = 1.0 \times 10^{-16} ; (At. \ wt. \ Ag = 108; I = 127)$]