It might not be well known, but there is a desert in North America. It spans along the western side of the continent, from southern Oregon to northern Mexico. It is mostly contained in the arid area between the Rocky Mountains to the east and the fertile coast of the Pacific Ocean to the west. Researchers estimate that the desert is between 500,000 and 730,000 square miles (1,300,000 and 1,900,000 square kilometres). People do live in this desert, but the pockets of people are dispersed and isolated. As a desert, the area is arid because of high evaporation, extreme temperatures, high winds, localized storms, and sun-beaten land. Life is a struggle in the desert for humans, as well as plants and animals. There are still descendants of indigenous desert cultures living in the desert. These Native Americans, along with European settlers, have added to the population of the region.

In the desert, differences of latitude, elevation, climate, topography, vegetation, soil, and human use have divided the desert into a cold region and a hot region. The cold region of the desert is known as the Great Basin Desert. This area covers almost all of Nevada, western Utah, and sections of the neighboring states. South of this basin is the Mojave Desert, which is the hot region of the North American Desert. This area covers much of California, southern Nevada, and some of Mexico.

Select the reason the author included the point that there are still descendants of indigenous desert cultures in the desert.

a
To show there are a lot of people in the desert

b
To show there are a lot of plants in the desert

c
To show there are people still living in the desert

d
To show there are animals still living in the desert