The correct order of reactivity in electrophilic substitution reaction of the following compounds is:

Step-by-step solution

Nitrobenzene shows - M effect. In nitrobenzene, it is known that the nitro group is an electron-withdrawing species, and therefore, it comes under the category of deactivating species. Thus, it favours meta-position for the upcoming substitution in benzene ring since deactivating groups have higher electron density in meta position than ortho and para position. Thus, the electrophilic substitution reaction for nitrobenzene is meta-directing. Chlorobenzene shows - I effect. Cl shows a negative inductive effect due t