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(C) The rate of nucleophilic aromatic substitution $(S_NAr)$ reaction depends on the stability of the Meisenheimer complex formed as an intermediate.

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$v > iii > i > ii > iv$

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(C) The rate of nucleophilic aromatic substitution $(S_NAr)$ reaction depends on the stability of the Meisenheimer complex formed as an intermediate. Electron-withdrawing groups (EWGs) like $-NO_2$ stabilize the negative charge in the intermediate through $-I$ and $-M$ effects.$1$. The presence of more $-NO_2$ groups increases the rate of $S_NAr$ reaction.$2$. The $-NO_2$ group at ortho and para positions is more effective than at the meta position because the negative charge can be delocalized onto the oxygen atoms of the $-NO_2$ group.Comparing the compounds:$(v)$ $2,4,6$-trinitrochlorobenzene: Three $-NO_2$ groups (two ortho,one para) - Fastest.(iii) $2,4$-dinitrochlorobenzene: Two $-NO_2$ groups (one ortho,one para).$(i)$ $p$-nitrochlorobenzene: One $-NO_2$ group at para position.(ii) $m$-nitrochlorobenzene: One $-NO_2$ group at meta position (less effective stabilization).(iv) Chlorobenzene: No $-NO_2$ group - Slowest.Therefore,the decreasing order of the rate of $S_NAr$ reaction is: $v > iii > i > ii > iv$.

Arrange the following compounds in decreasing order of their rate of $S_NAr$ reaction:
$(i)$ $p$-nitrochlorobenzene
(ii) $m$-nitrochlorobenzene
(iii) $2,4$-dinitrochlorobenzene
(iv) chlorobenzene
$(v)$ $2,4,6$-trinitrochlorobenzene

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Arrange the following compounds in decreasing order of their rate of $S_NAr$ reaction:$(i)$ $p$-nitrochlorobenzene(ii) $m$-nitrochlorobenzene(iii) $2,4$-dinitrochlorobenzene(iv) chlorobenzene$(v)$ $2,4,6$-trinitrochlorobenzene