Which of the following principles was included in most state constitutions?

A. Separation of Powers

B. Judicial Review

C. Parliamentary structure

D. Popular Sovereighnty

I believe the answer is: D. Popular Sovereignty

Popular sovereignty refers the principle of government which ruled by the will from the majority of the people.

In democratic country such as united states (and most of the countries in western hemisphere), this would be included in most state constitutions.