The increasing order of reactivity of the following compounds towards reaction with alkyl halides directly is:

The reactivity is directly proportional to the localized electron density and availability of the lone pair on the nitrogen atom:

• (ii) Phthalimide: The nitrogen lone pair is strongly delocalized across two adjacent electron-withdrawing carbonyl groups via resonance, making it the least nucleophilic.
• (i) Benzamide: The nitrogen lone pair is delocalized into one carbonyl group via amide resonance, leaving it highly unavailable but slightly more active than a di-acyl amide.
• (iii) p-Cyanoaniline: The lone pair is delocalized into the aromatic ring, which is further deactivated by the strong electron-withdrawing cyano group ($$-\text{C}\equiv\text{N}$$), reducing its overall nucleophilicity.
• (iv) Aniline: The nitrogen lone pair undergoes normal delocalization into an unsubstituted benzene ring, maintaining the highest nucleophilic character among the group.

Conclusion:

As the electron-withdrawing capability of the attached functional groups decreases, the availability of the nitrogen lone pair increases correspondingly.

Answer: Option B — (ii) < (i) < (iii) < (iv)