Explanation:

Option A: There can be large number of citizens even in an autocratic state.

Option B: Not every democracy is based on a constitution, and not every constitutional state is a democracy.

Option C: Restrictions on the freedom of individuals may come from domination and external controls. Such restrictions may be imposed by force or they may be imposed by a government through laws which embody the power of the rulers over the people and which may have the backing of force. Some form of government may be inevitable but if the government is a democratic one, the members of a state could retain some control over their rulers. That is why democratic government is considered to be an important means of protecting the freedom of people.

Option D: Not every democracy has the provision of referendum, which is public voting on major governmental decisions. It is a feature found mostly in direct democracies.