Answer:
The correct answer is: cities.
Step-by-step explanation:
The most important characteristics of civilizations are cities, government, religion, social structure, writing, and architecture.
Each civilization is characterized by administrative infrastructure, urban areas, common methods of communication and division of labor.
Therefore, every civilization must contain:
1) cities – large population centers and urban areas that are constantly developing ;
2) government – a system used for administering territories ;
3) religion – a social-cultural system of worldviews, prophecies, ethics or behaviors that relate one civilization to some spiritual or transcendental elements;
4) social structure – the division of people into classes and division of labor .
5) writing – shared communications strategies (alphabet, numeric system, symbols (illustration and representation);
6) architecture – monuments and authentic art styles.