Question

. Read the paragraph and choose a sentence that describes it best. When most people imagine an archetypal desert landscape—with its relentless sun, rippling sand and hidden oases—they often picture the Sahara. But 11,000 years ago, what we know today as the world’s largest hot desert would’ve been unrecognizable. The now-dessicated northern strip of Africa was once green and alive, pocked with lakes, rivers, grasslands and even forests. So where did all that water go? The Sahara has long been subject to periodic bouts of humidity and aridity. These fluctuations are caused by slight wobbles in the tilt of the Earth’s orbital axis, which in turn changes the angle at which solar radiation penetrates the atmosphere. At repeated intervals throughout Earth’s history, there’s been more energy pouring in from the sun during the West African monsoon season, and during those times—known as African Humid Periods—much more rain comes down over north Africa.

a) Sahara will turn green again in some time, and humans cannot influence this
b) Changes in the Earth’s axis cause the changes of Sahara climate
c) The deserts are produced by the changes of the Earth’s axis
d) The water reducing caused Sahara to become a desert

Answer 1

The best sentence that describes the paragraph about the Sahara desert is that the changes in the Earth's axis are responsible for the climate changes in the region, causing it to transform from a lush area into the arid desert that is present today. The correct choice of action is b) Changes in the Earth’s axis cause the changes of Sahara climate.

Step-by-step explanation:

Based on the paragraph provided, the sentence that best describes it is: Changes in the Earth’s axis cause the changes of Sahara climate. The given paragraph explains that the Sahara was not always a desert; it used to be a lush region with lakes, rivers, grasslands, and forests.

The transformation to a desert landscape, characterized by its dry and arid conditions, was influenced by fluctuations in humidity and aridity caused by slight wobbles in the tilt of the Earth’s orbital axis, which affected the solar radiation and, consequently, the rainfall in North Africa. These changes resulted in the Sahara experiencing periods known as African Humid Periods, during which it received more rain. However, with a shift away from these conditions, the region dried up, leading to the vast desert we recognize today.