When acetylene is passed through red hot iron tube , compound ‘X’ is formed. Which one of the    following reactions will yield ‘X’ as major product?

Acetylene on passing through red hot iron tube at 873K undergoes cyclic polymerization. Three of the acetylene molecules polymerize to form benzene.

${\mathrm{C}}_6{\mathrm{H}}_5{\mathrm{SO}}_3\mathrm{H}+{\mathrm{NaHCO}}_3\to {\mathrm{C}}_6{\mathrm{H}}_5{\mathrm{SO}}_3^{-}{\mathrm{Na}}^{+}+{\mathrm{H}}_2\mathrm{O}+{\mathrm{CO}}_2$

${\mathrm{C}}_6{\mathrm{H}}_5\mathrm{Cl}+{\mathrm{H}}_2\mathrm{O}\stackrel{∆}{\to }{\mathrm{C}}_6{\mathrm{H}}_5\mathrm{OH}+\mathrm{HCl}$

${\mathrm{C}}_6{\mathrm{H}}_{12}+3{\mathrm{H}}_2\stackrel{\mathrm{Ni}}{\to }\mathrm{No} \mathrm{reaction}$

${\mathrm{C}}_6{\mathrm{H}}_5\mathrm{COONa}+\mathrm{NaOH}\underset{∆}{\overset{\mathrm{CaO}}{\to }}{\mathrm{C}}_6{\mathrm{H}}_6+{\mathrm{Na}}_2{\mathrm{CO}}_3$