Solution:

Electrophiles are reagents that take part in a response by tolerating a couple of electrons to tie to nucleophiles.

The higher the thickness of electrons on a benzene ring, the more receptive the compound is to an electrophile, E+ (Electrophilic response).

The electron thickness of the fragrant ring diminishes because of the presence of an electron-pulling out bunch (i.e., NO2 – and Cl – ) which deactivates the sweet-smelling ring.

Since, Cl – bunch is less electron-pulling out (because of the inductive impact) than NO2 – bunch (because of reverberation impact), the expanding request of reactivity is as per the following:

2, 4 – dinitrochlorobenzene < p – nitrochlorobenzene < Chlorobenzene