Final answer:
The political cartoon symbolizes the Soviet Union's suppression of the Prague Spring reforms in Czechoslovakia under the guise of 'protection,' when in fact the Soviet motive was to maintain control over the Eastern Bloc.
Step-by-step explanation:
The message of the 1969 British political cartoon featuring a large Soviet man taking away a man in chains with a sign labeled Czechoslovakia is a commentary on the Soviet Union's suppression of democratic reforms in Eastern Europe, particularly the intervention in Czechoslovakia in 1968. The correct answer to the question, which asks for the message of the cartoon, would be 'd. The Soviets believe that Dubček's reforms might free Czechoslovakia from their control.' This is in the context of the Prague Spring and the subsequent invasion of Czechoslovakia by the Soviet Union to halt the reforms initiated by Alexander Dubček that were leading to a more liberalized and possibly independent Czechoslovakia.
The Brezhnev Doctrine justified such actions to maintain communist control over Eastern Bloc countries, painting the suppression as a form of 'protection'. The irony in the cartoon is palpable, suggesting that the excuse of 'protection' is merely a pretense for stifling freedom and maintaining Soviet control. This is contrasted with later events, such as the Velvet Revolution and the policies of Mikhail Gorbachev, who allowed Eastern European countries to transition to democracy without military intervention.