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The correct statement regarding the basicity of arylamines is
A
Arylamines are generally more basic than alkylamines because the nitrogen lone-pair electrons are not delocalized by interaction with the aromatic ring $\pi$-electron system.
B
Arylamines are generally more basic than alkylamines because of aryl group.
C
Arylamines are generally more basic than alkylamines, because the nitrogen atom in arylamines is sp-hybridized.
D
Arylamines are generally less basic than alkylamines because the nitrogen lone-pair electrons are delocalized by interaction with the aromatic ring $\pi$-electron system.
Explanation
Delocalisation of the N lone pair into the ring lowers basicity.
Detailed Solution
In alkylamines ($R\rightarrow\ddot{N}H_2$), the electron-releasing alkyl group increases electron density on nitrogen, so alkylamines donate the lone pair readily and are more basic.
In arylamines ($Ar-\ddot{N}H_2$), the lone pair on nitrogen is in conjugation with the ring (+M effect overpowers –I); it is delocalised into the ring and stabilised by resonance.
Therefore the tendency to donate the lone pair decreases, i.e. arylamines are less basic than alkylamines.
In arylamines ($Ar-\ddot{N}H_2$), the lone pair on nitrogen is in conjugation with the ring (+M effect overpowers –I); it is delocalised into the ring and stabilised by resonance.
Therefore the tendency to donate the lone pair decreases, i.e. arylamines are less basic than alkylamines.