Which was not a development of 1949? a. the soviets formalized their own eastern european alliance, the warsaw pact. b. nato was established. c. mao zedong emerged victorious in the long chinese civil war. d. the soviet union tested its first atomic bomb?

The correct answer is A.

The Warsaw Pact was a response to the United States developing the North Atlantic Treaty Organization in 1949. However, this alliance of Soviet influenced states did not take place until West Germany officially became a member of NATO. This is when the Soviet Union officially formed the Warsaw Pact. The year in this case was 1955.