Answer:
A) The flooding of rivers created good farmland.
Step-by-step explanation:
This is the answer because:
Civilizations began in the river valleys for many reasons. One reason why the start of civilization began in the river valleys is because the waters in the rivers flow slowly, allowing them to collect silt. When the rivers overflow their banks, the rivers bring fresh soil to the river valley. Silt is sediment that is deposited on farmland by rivers which acts as a fertilizer. This soil is great for farming. People settled in the valley to also grow crops and raise livestock.
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