Select reagent(s) which is/are used in laboratory t-0 differentiate 1°, 2° and 3° amines from each other:

(a) $1^{\circ }\underset{\mathrm{HCl}}{\overset{\stackrel{ }{{\mathrm{NaNO}}_2}}{\to }}\mathrm{R}-\mathrm{OH} \stackrel{\mathrm{C}.\mathrm{A}.\mathrm{N}}{\to }. > (\mathrm{Red} \mathrm{Colour}\hspace{0.17em})$

$2^{\circ }\stackrel{ }{\underset{\mathrm{HCl}}{\overset{{\mathrm{NaNO}}_2}{\to }}}\mathrm{R}-\mathrm{N}-\mathrm{N}=\mathrm{O}\text{ (Oily liquid) }$

$3^{\circ }\stackrel{ }{\underset{\mathrm{HCl}}{\overset{{\mathrm{NaNO}}_2}{\to }}}\text{ Salt }$

(b) Hinsberg's test can distinguish 1°, 2° and 3° amines.

(c) Carbylamine test is given by only 1° amines. 

(d) Mustard oil reaction is also given by 1° amine only.