Select the member$(s)$ of group $14$ that $(i)$ forms the most acidic dioxide,$(ii)$ is commonly found in $+2$ oxidation state,$(iii)$ used as semiconductor.

(N/A) $(i)$ Carbon ($CO_2$ is the most acidic dioxide).
$(ii)$ Lead ($Pb$ shows inert pair effect and is stable in $+2$ oxidation state).
$(iii)$ Silicon and Germanium (both are widely used as semiconductors).