The correct answer is (b). In the Marxist understanding, the state is an organ of class rule.
While bourgeois theorists tend to see the state as a set of institutions above and beyond classes and capable of reconciling different interests, Marxists recognize it as an organ for the oppression of one class by another. Engels states that the state is a “special coercive force”. It holds the exclusive right to use violence to maintain class rule and consists of special bodies of armed men having prisons, etc. at their command. The best form of the state for the capitalist class is a “democratic” shell where wealth exercises its power indirectly, but all the more surely. Speaking of the capitalist state, Lenin says “It establishes its power so securely, so firmly that no change in persons, institutions or parties in the bourgeois-democratic republic can shake it.” The capitalist class will resort to an undemocratic form when its class rule is in jeopardy. It can and has resorted to brutal militaristic dictatorship and force (fascism), to protect its interest.
The state is distinct from the government. Governments change rapidly, based on the results of elections (or the outcomes of coups), but only revolution can change the class basis of state power. In some sense, the government is a terrain of class struggle. The process of forming governments registers the relative strength of different class and social forces; by changing the composition of the government (i.e., from conservative to progressive), the working class can place some limits on how the capitalist class wields state power.