D certainly has happened. But like the Phoenix both Russia (communist) and Germany (socialist) rose again out of the ashes -- modified and stronger, at least in the case of Russia.
C is your answer and it is a very good summary of both of them.
B Russia has a token Representative Assembly. I'm not sure what the Duma can or cannot do, but I'm sure the real power resides elsewhere.
A While A is true (just as it is in the United States) the best answer is C. That is a much better answer.