How did silt influence the development of civilizations in the fertile crescent? (1 point)
soil eroded from old volcanoes blended with tigris river mud to enrich the soil.
floodwaters from melting mountain snow left silt that improved the soil.
spring coastal rains of silt moistened and fertilized dry river valley soil.
annual floodwaters in the nile delta washed silt inland to build up the soil.