When $B_2H_6$ reacts with $H_2O$ or alkalies and produces $x+y$ is liberated.The $x$ is

Question

$\begin{array}{1 1}(a)\;Boric\;acid\\(b)\;Metaboric\;acid\\(c)\;Hydro\;chloric\;acid\\(d)\;Tetraboric\;acid\end{array}$