Match the catalysts (column I) with products (column II).

column I	column II
(I) $V_2{O}_5$	(a) Manufacture of polymers of alkenes
(II) $\mathrm{Al}({\mathrm{C}}_2{\mathrm{H}}_5{)}_3+{\mathrm{TiCl}}_4$	(b) Manufacture of ethanal
(III) ${PdCl}_2$	(c) Manufacture of ${\mathrm{H}}_2{\mathrm{SO}}_4$
(IV) Iron	(d) Manufacture of ${\mathrm{NH}}_3$

$V_2{O}_5$ is used as a catalyst in contact process for manufacture of ${\mathrm{H}}_2{\mathrm{SO}}_4. {\mathrm{TiCl}}_4/\mathrm{Al}({\mathrm{C}}_2{\mathrm{H}}_5{)}_3$ is Ziegler–Natta catalyst is a type of catalyst that are mainly used in polymerization of alkenes.

PdCl₂ is used in Wacker process, in which alkene changed into aldehyde via catalytic cyclic process initiated by PdCl₂.

In Haber’s process for manufacture of ammonia, molybdenum acts as a promoter for iron which is used as a catalyst.

Therefore, option A is correct.