Question #N289

In the early 1900s, European settlers in the American West often used a technique called "dry farming" to cultivate land in arid regions. Dry farming involved tilling the soil deeply and leaving it exposed to the sun in order to create a dust mulch that would help retain moisture. It was believed that this technique would allow farmers to grow crops without relying on irrigation.

What is the main idea of this passage?
A. Dry farming was a technique used by European settlers in the American West to cultivate land in arid regions.
B. Dry farming involved tilling the soil deeply and leaving it exposed to the sun to create a dust mulch that would help retain moisture.
C. European settlers in the American West often used dry farming to grow crops without relying on irrigation.
D. Dry farming was a technique used to retain moisture in arid regions by tilling the soil deeply and leaving it exposed to the sun.