$\begin{array}{1 1} \text{(a) The transformation of solid to liquid is called melting and the reverse process is called freezing} \\ \text{
(b) The transformation of solid to liquid is called freezing and the reverse process is called melting} \\ \text{
(c) The transformation of liquid to solid is called melting and the reverse process is called freezing} \\ \text{
(d) None of the mentioned}
\end{array} $
