Final answer:
The Fertile Crescent refers to a region in the Middle East shaped like a crescent where early civilizations flourished along the Tigris, Euphrates, and Nile rivers.
Step-by-step explanation:
The Fertile Crescent refers to B) Civilizations which developed along rivers to the Mediterranean Sea to the Persian Gulf.
An area known as the Fertile Crescent is a crescent-shaped region in the Middle East where some of the world's earliest civilizations developed. Surrounded by the Tigris and Euphrates rivers, this region's abundant water supply and fertile land allowed for the birth of agriculture during the Neolithic Revolution. Agriculture laid the foundation for the emergence of civilizations because it led to the growth of food surplus, which in turn spurred population growth, social stratification, and the development of cities.
Famous cities such as Ur, Babylon, and Nineveh prospered here due to their sophisticated irrigation and agricultural systems. The Fertile Crescent extended from the Persian Gulf, up through modern-day Iraq, Syria, Lebanon, Jordan, Israel, and Egypt, where it reached the Nile River.