Which of the following is the strongest meta-directing group?

Assertion : $p-$nitroacetophenone $(p-O_2N-C_6H_4-COCH_3)$ is prepared by Friedel-Crafts acylation of nitrobenzene.
Reason : Nitrobenzene easily undergoes electrophilic substitution reaction.

Consider the reaction of $1-chloro-2-hydroxy-4-nitrobenzene$ with $OH^-$ followed by $H^+$. Based on the above reaction,the major product $P$ would be:

How will you convert $4-$nitrotoluene to $2-$bromobenzoic acid?

The correct order of reactivity for the reaction involving the cleavage of the $C-X$ bond in the following compounds is:

$(i)$ chlorobenzene is mono-nitrated to $M$.
$(ii)$ nitrobenzene is mono-chlorinated to $N$.
$(iii)$ anisole is mono-nitrated to $P$.
$(iv)$ $2-$nitrochlorobenzene is mono-nitrated to $Q$.
Out of $M$,$N$,$P$ and $Q$,the compound that undergoes reaction with $aq. NaOH$ fastest is: