Correct Option: B

The Union of Soviet Socialist Republics of Soviet Union was a constitutionally socialist state that existed between 1922 and 1991, ruled as a single-party state by the Communist Party with its capital as Moscow. On 25 December, 1991, the USSR was dissolved into 15 post-Soviet states. The Russian Federation, successor of the Russian SFSR, assumed the Soviet Union’s rights and obligations and is recognised as its continued legal personality.