Isomeric amines with molecular formula $C_8H_{11}N$ give the following tests:
Isomer $(P) \Rightarrow$ Can be prepared by Gabriel phthalimide synthesis.
Isomer $(Q) \Rightarrow$ Reacts with Hinsberg's reagent to give a solid insoluble in $NaOH$.
Isomer $(R) \Rightarrow$ Reacts with $HONO$ followed by $\beta$-naphthol in $NaOH$ to give a red dye.
Isomers $(P), (Q)$ and $(R)$ respectively are:

• A
  
• B
  
• C
  
• D