Amongst the following the most basic compound is:

Basicity depends on the availability of the lone pair on Nitrogen.In Aniline and its derivatives, the lone pair is delocalized into the benzene ring.In Benzylamine (${\text{C}}_6{\text{H}}_5{\text{CH}}_2{\text{NH}}_2$), the $-{\text{NH}}_2$ group is not directly attached to the ring, so its lone pair is fully available, making it the most basic.