Choose the incorrect option from the following.

Alkyl diazonium salts are highly unstable

Aryl diazonium salts are stable at very low temperature 

Aryl diazonium salts are less stable than alkyl diazonium salts

${\mathrm{C}}_6{\mathrm{H}}_5{\mathrm{N}}_2^{+}{\mathrm{HSO}}_4^{-}$ is named as benzene diazonium hydrogen sulphate