c
\(Ca{C_2}\xrightarrow{{{H_2}O}}\mathop {{C_2}{H_2}}\limits_{(A)} \xrightarrow[{{H_3}{O^ \oplus }}]{{H{g^{ + 2}}}}\) \(\mathop {\begin{array}{*{20}{c}}
{\,\,\,\,\,\,\,\,O} \\
{\,\,\,\,\,\,\,\,\,||} \\
{C{H_3}CH}
\end{array}}\limits_{(B)} \xrightarrow[{{H_2}}]{{Ni}}\mathop {C{H_3} - C{H_2} - OH}\limits_{(C)} \)