Which among the following has the lowest boiling point?

Identify the product '$$\mathrm{B}$$' in the following reaction.

Dry ice $$\mathrm{\mathrel{\mathop{\kern0pt\longrightarrow} \limits_{Dry\,ether}^{C{H_3}MgBr}}}$$ A $$\mathrm{\mathrel{\mathop{\kern0pt\longrightarrow} \limits_{dil.\,HCl}^{{H_2}O}}}$$ B

Identify the product 'B' in the following series of reactions.

$$\mathrm{CH_3COOH+CH_3CH_2OH}$$ $$\stackrel{\mathrm{H}^{+}}{\rightleftharpoons} A \xrightarrow[\mathrm{Ni} / \mathrm{Pd}, \Delta]{\mathrm{H}_2}$$ B

Which of the following carboxylic acids has lowest boiling point?