After farmers in the fertile crescent developed techniques to transfer water, people no longer needed to
a. turn to agriculture
b. settle next to a river
c. dig irrigation ditches
d. travel to southern mesopotamia

The correct answer is B. Settle next to a river.

Explanation

The Fertile Crescent is a region that encompasses North Africa (Nile Delta) and the Middle East (Mesopotamia) in which agriculture and irrigation systems were developed that allowed increasing areas of fertile soil through the transfer of water from a water source like rivers. These irrigation systems were based on the canalization of the river, taking advantage of its flow and its direction, to make them reach areas moderately far from the mainstream. So, the correct answer is B. Settle next to a river.

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