How should the relation between Comintern and communist parties be understood?

Correct answer: Comintern was an international platform that tried to connect communist parties.

The governing concept is international coordination within the communist movement. The Communist International, commonly called the Comintern, was created after the Russian Revolution to promote cooperation among communist organisations in different countries and to provide a forum for shared revolutionary discussion. It was not identical to every national party, but it sought to link and guide such parties within a wider movement. Option A is correct because it states this connecting and international role accurately. Options B, C and D are wrong: the Comintern was not a Tsarist army, communist parties were not Church branches, and both were explicitly connected with socialist politics.