Final answer:
Constitutions are not always written documents; some, like that of the United Kingdom, are a collection of various statutes, court judgments, and conventions.
Step-by-step explanation:
The statement among the options provided about constitutions that is untrue is: Constitutions are generally written. While many countries have written constitutions, not all countries do. The United Kingdom, for example, has an unwritten constitution made up of statutes, court judgments, and conventions.
Constitutions do indeed establish the basis of a political system, acting as a social contract between the state and its citizens.
They are also not static; they can be dynamic, changing with amendments and interpretations to meet the evolving needs of society.