The correct answer is D. Irrigation efforts have transformed dry land into farmland.
Explanation
As the map shows the northern area of Mexico is arid and semi-arid; however, this is not an obstacle to cultivate in this area because water irrigation processes are an alternative to make these areas more fertile. The irrigation process uses the water of natural origin, for example from rivers or underground reservoirs to make the soil more humid, allowing the planting of different species of plants. In addition, these waters have a high content of minerals that contribute to the fertile of the soils. Due to this, in the northern areas of Mexico, many people began to implement this process and were able to use it to plant areas that at first glance did not serve this purpose. So the correct answer is D. Irrigation efforts have transformed dry land into farmland.
