The correct answer is B, as a troika is a group of three governors.
In politics, a troika designates the alliance of three characters or entities of the same level and power that come together in a single effort to lead an entity or carry out a mission, similar to the old triumvirate of Rome. The term comes from the Russian troĭka (тройка), which designates a sled pulled by three horses aligned each side of the other. The Russian term was extended during the Russian Revolution to informally designate the most characteristic cell of Soviet power.