Amongst aldehyde & the acid derivatives, acid chloride are the most susceptible to nucleophilic attack due to strong $-\mathrm{I}$ effect & weak $+\mathrm{R}$ effect of the $\mathrm{C}\mathrm{l}-$ atom as a result of which carbonyl carbon has the highest electron deficiency. The actual order is

$\mathrm{M}\mathrm{e}\mathrm{C}\mathrm{O}\mathrm{C}\mathrm{l}>\mathrm{M}\mathrm{e}\mathrm{C}\mathrm{O}\mathrm{O}\mathrm{C}\mathrm{O}\mathrm{M}\mathrm{e}\mathrm{ }>\mathrm{M}\mathrm{e}\mathrm{C}\mathrm{O}\mathrm{O}\mathrm{M}\mathrm{e}\mathrm{ }>\mathrm{M}\mathrm{e}\mathrm{C}\mathrm{H}\mathrm{O}$ .