Identify substrate 'A' in the following reaction.

2nA $$\mathrm{\buildrel {Dimethyl\,cadmium} \over \longrightarrow}$$ 2n Propanone + n Cadmium chloride

Identify the reaction in which carbonyl group of aldehydes and ketones is reduced to methylene group on treatment with hydrazine followed by heating with sodium hydroxide in ethylene glycol.

Identify the product '$$\mathrm{B}$$' in the following reaction. Toluene $$\xrightarrow[\mathrm{CS}_2]{\text { Chromylchloride }} \mathrm{A} \xrightarrow{\mathrm{H}_3 \mathrm{O}^{+}}\mathrm{B}$$

Which among the following is a simple ketone?