Which one of the following compound undergoes decarboxylation most readily.

$\mathrm{\beta }$- keto carboxylic acids readily undergo decarboxylation.

EWG always increase the ease of decarboxylation. In fact these compounds undergo decarboxylation even on heating.

${\mathrm{CH}}_3-\stackrel{\underset{\left|\right|}{\mathrm{O}}}{\mathrm{C}}-{\mathrm{CH}}_2-\mathrm{COOH}\stackrel{∆}{\to }{\mathrm{CH}}_3-\stackrel{\underset{\left|\right|}{\mathrm{O}}}{\mathrm{C}}-{\mathrm{CH}}_3+{\mathrm{CO}}_2$