Question

Predict the correct intermediate and product in the following reaction :${\mathrm{H}}_3\mathrm{C}-\mathrm{C}\equiv \mathrm{CH}\underset{{\mathrm{HgSO}}_4}{\overset{{\mathrm{H}}_2\mathrm{O}, {\mathrm{H}}_2{\mathrm{SO}}_2}{\to }}\underset{\left(\mathrm{A}\right)}{\mathrm{Intermediate}}\underset{}{\to }\underset{\left(\mathrm{B}\right)}{\mathrm{product}}$