Identify the alkyne in the following sequence of reactions,

Alkyne$\underset{\mathrm{Lindlar}\text{'}\mathrm{s} \mathrm{catalyst}}{\overset{{\mathrm{H}}_2}{\to }}$A$\stackrel{\mathrm{ozonolysis}}{\to }$B(only)$\stackrel{\mathrm{Wacker}\text{'}\mathrm{s} \mathrm{process} \mathrm{only}}{\leftarrow }$CH₂$=$CH₂

 

In Wacker process, alkenes is oxidized into aldehyde

Since on ozonolysis, only alkenes produce aldehydes, ‘A’ must be an alkene that undergoes ozonolysis, bring the products together in such a way that O atoms are face to face and, replace O by double (=) bond. Thus,