The correct answer is B) The availability of once classified diplomatic and political documents
What led to a revisionist history of the Cold War was the availability of once classified diplomatic and political documents.
Historical revisionist implies that history has to be reviewed with a critical eye in order to analyze all the elements, characters and dates in order to prove that the historical facts were real or at least as were originally told. That is why, in this case, the availability of once classified diplomatic and political documents could open new doors for investigation and find things never before considered.
