The correct option is A Democracy
A democracy is a system of government by the whole population or all the eligible members of a state, typically through elected representatives. For example, "a system of parliamentary democracy". Hence, Option B is correct. Among the rest of the options, diplomacy means the profession, activity, or skill of managing international relations, typically by a country's representatives abroad, socialism means a political and economic theory of social organization which advocates that the means of production, distribution, and exchange should be owned or regulated by the community as a whole, autocracy means a system of government by one person with absolute power. These options do not express this meaning, hence incorrect.