Answer:
A) the weak economy of the former East Germany
Step-by-step explanation:
The economy of the former East Germany was the main factor that contributed to the collapse of communism in Germany.
The economy of East Germany, like the economy of all the other communist states of the time (the Soviet Union, Czeckolosvakia, Yugoslavia, Hungary, etc) was doing very poorly, even if East Germany was the wealthiest nation of the bloc.
People from East Germany were using Hungary as a means to emigrate to West Germany, and this flow of people became harder to control with time.
Finally, the pressure led to the fall of the Wall of Berlin in 1989, and shortly after, the dissolution of the former East Germany, whose territories were unified with West Germany.