Arrange the following events related to disintegration of the Soviet Union in chronological order:

(A) Boris Yeltsin is appointed as the head of the Communist Party in Moscow.
(B) Soviet Union declares that the Warsaw Pact members are free to decide their own future.
(C) Boris Yeltsin becomes the President of Russia.
(D) The Commonwealth of Independent States is established.

Choose the correct answer from the options given below:

(A), (B), (C), (D)

The correct answer is Option (1) → (A), (B), (C), (D)

(A) Boris Yeltsin is appointed as the head of the Communist Party in Moscow. 1985
(B) Soviet Union declares that the Warsaw Pact members are free to decide their own future. 1989
(C) Boris Yeltsin becomes the President of Russia. June 1991
(D) The Commonwealth of Independent States is established. December 1991