Answer:
Among the options given on the question, the answer is option D.
The countries of the communist bloc had separated from the Soviet Union,so they no longer took part in the pact.
Explanation: The Warsaw Pact was signed on 1955 by Soviet Union and the eastern European communist allies as a response to the NATO formed by United States, Canada and their Western European allies. NATO was formed on 1949. The countries who signed on Warsaw pact were USSR, East Germany,Hungary, Albania, Poland,Romania, Bulgaria, Czechoslovakia. However this pact was dissolved on 1991 because of the countries from Communist bloc started to separate them from the Soviet ally. East Germany took off their name from the pact as they got unite with west Germany. Poland and Czechoslovakia also showed their strong indication to leave the pact.
On the other hand Soviet Union was also becoming politically and economically week. So on 1991 the the Soviet commanders announced their relinquishment from the pact. After a few months later a formal meeting was arranged and the Warsaw Pact was dissolved.
