$\begin{array}{1 1} \text{(a) $H_3PO_3$ is dibasic and reducing} \\ \text{ (b) $H_3PO_3$ is dibasic and non-reducing} \\ \text{ (c) $H_3PO$ is tribasic and reducing} \\ \text{ (d) $H_3PO_3$ is tribasic and non-reducing } \end{array} $