Statement $I:$ Primary aliphatic amines react with $HNO _{2}$ to give unstable diazonium salts.
Statement $II:$ Primary aromatic amines react with $HNO _{2}$ to form diazonium salts which are stable even above $300 \,K$.
In the light of the above statements, choose the most appropriate answer from the options given below:

$R - \mathop {\mathop {C\,N{H_2} \to RC{H_2}N{H_2}}\limits^{||\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} }\limits^{O\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} $

