Before the Dust Bowl, prairie grass held soil down during high winds and kept moisture in during times of drought.
Option: A
Step-by-step explanation:
Dust bowl created at the time of great depression. It promotes dry weather which causes excess soil erosion. Dry soil easy to erode by the action of wind. Before the creation of dust bowl prairie grass land holds the soil by deep roots of grass lands.
Grass lands hold the moisture of the soil at its adequate level but when dust bowl was created it reduces the moisture level turned the soil excessive dry and eroded it highly. Dust bowl creation was very harmful for the environment as it was destroyed the environment.