Consider the following aryl halides toward hot aqueous $\mathrm{NaOH}$ (nucleophilic aromatic substitution): I, chlorobenzene; II, 1-chloro-4-nitrobenzene; III, 1-chloro-2,4-dinitrobenzene; IV, 2-chloro-1,3,5-trinitrobenzene. The correct order of increasing reactivity is

1. A$\mathrm{I}<\mathrm{III}<\mathrm{II}<\mathrm{IV}$
2. B$\mathrm{IV}<\mathrm{III}<\mathrm{II}<\mathrm{I}$
3. C$\mathrm{II}<\mathrm{I}<\mathrm{III}<\mathrm{IV}$
4. D$\mathrm{I}<\mathrm{II}<\mathrm{III}<\mathrm{IV}$