$ \begin{array}{1 1}(a)\;pK_b^0\text{(aniline) is less than }pK_b^0\text{(P-nitro aniline)}\\(b)\;pK_b^0\text{(aniline) is more than }pK_b^0\text{(P-amino aniline)}\\(c)\;\text{amines are less basic than water and also less basic than hydroxidation}\\(d)\;\text{Aliphatic amines are more basic than ammonia}\end{array}$