Which of the following reactions yields biphenyl from chlorobenzene?

Identify the major product obtained in the following reaction.
Chlorobenzene $\xrightarrow[\text{Anhydrous } FeCl_3]{Cl_2}$ major product

Why are aryl halides less reactive towards nucleophilic substitution reactions than alkyl halides? How can we enhance the reactivity of aryl halides?

Acetanilide $\xrightarrow[{CH_3COOH}]{{Br_2}}$ major product will be

The major product formed in the Friedel-Crafts acylation of chlorobenzene is $p-$chloroacetophenone. Identify the correct structure of the major product.

Haloarenes are less reactive than haloalkanes and haloalkenes towards nucleophilic substitution reactions. Explain.