Question

to help combat blowing sand, the soil erosion service and the prairie states forestry project put many men to work doing what?
a. planting trees.
b. digging ditches.
c. spraying water on the soil
d. none of the above.

Explanation:

Trees can act as windbreaks. Their roots can hold the soil together and their trunks and branches can reduce the speed of the wind, thus helping to combat blowing sand. Digging ditches (option b) is more related to water drainage. Spraying water on the soil (option c) is a temporary measure and not a long - term solution like tree - planting for combating blowing sand.

Answer:

A. Planting trees.