Answer:
B. River valley
Step-by-step explanation:
One of the most important features for the beginning of a civilization is a river valley. The availability of water is crucial for the development of agriculture, and a river valley provides a reliable source of water as well as fertile land for farming. The river also enables transportation and trade, allowing for the growth of trade and the exchange of goods and ideas. Additionally, the river can provide protection from invasion, as the civilization can build their cities and settlements along its banks, making it harder to attack. Many of the world's earliest civilizations, such as the Mesopotamians, the Egyptians, and the Indus Valley Civilization, developed in river valleys.