The correct answer is C.
The nitro group is a meta-directing group in electrophilic aromatic substitution reactions because it is an electron-withdrawing group. Electron-withdrawing groups destabilize the benzene ring by withdrawing electron density
from the ring. This makes the ortho and para positions less reactive towards electrophiles, and the meta position more reactive.Option A is incorrect because the nitro group decreases electron density at the ortho and para positions.
Option B is incorrect because the nitro group does not increase electron density at the ortho and para positions.
Option D is incorrect because the nitro group does not decrease electron density at the meta position.