The correct increasing order of basic strength for the following compounds is:

Basicity of amines depends on the availability of the lone pair on nitrogen.Electron-withdrawing groups (EWG) decrease basicity, while electron-donating groups (EDG) increase it.$-{\text{NO}}_2$ (in II) is a strong EWG ($-M,-I$), significantly reducing basicity.$-{\text{CH}}_3$ (in III) is an EDG ($+I$, hyperconjugation), increasing basicity compared to aniline.Increasing order: $p$ -nitroaniline (II) < Aniline (I) < $p$ -toluidine (III).