The correct option is
C 2-butyne
Kolbe electrolysis is a electrochemical decarboxylation of the salts of carboxylic acid which produces radicals. This reaction is also called as decarboxylative dimerisation since it proceeds with radical reaction mechanism. This reaction is used in synthesis of symmetrical dimers.
Above compound forms radicals and undergoes decarboxylation to give 2-butyne.