Which of the following compounds has difficulty in breaking \(\mathrm{C}-\mathrm{X}\) bond?

In aryl halide, \(\mathrm{X}\) atom is attached with \(\mathrm{sp}^2(\mathrm{C})\), the \(\mathrm{C}-\mathrm{X}\) bond in aryl halide is shorter than in alkyl halides. This makes \(\mathrm{C}-\mathrm{X}\) bond stronger in aryl halides.
Under normal conditions, halobenzene's are inert to nucleophiles. However, Chlorobenzene can be made to react if the experimental conditions are:
1. High temperature and high pressure.
2. In presence of strong electron-withdrawing \(\left(-\mathrm{NO}_2\right)\) substituent at ortho and/or para positions.
Thus, \(\mathrm{m}-\) nitrochlorobenzene has difficulty in breaking \(\mathrm{C}-\mathrm{X}\) bond.