More than two thousand years ago, a people the Romans, called the Garamantes, created a complex civilization in one of the world’s driest places—the Sahara Desert. Beginning around 500 BCE, they built towns and villages, cloth was manufactured there and jewelry, and traded throughout North Africa and the Mediterranean. They also grew a variety of crops, including wheat, dates, palms, grapes, figs, and melons.(18)
The survival of their civilization depended on hundreds of miles of underground tunnels. These tunnels carried water to desert settlements from an aquifer, an underground water source, in the distant mountains.
The water ran through sloping, hand-dug tunnels called foggaras, which could be as deep as one hundred thirty feet below ground. These tunnels were connected to the surface by ventilation shafts every thirty feet or so. When the tunnels reached a town or field, the water flowed into more easy accessible surface canals or reservoirs. Having left no clues, archaeologists don’t know how the Garamantes learned to build foggaras. Other such tunnels exist in Iran, Algeria, Tunisia, and elsewhere.
Because the canals were underground, the water they carried stayed clean and didn’t evaporate. And because the water came from an aquifer rather then form its rainfall, the supply was unaffected by drought. The Garamantes could of relied on a constant supply of water for drinking, washing, and irrigation. Moreover, the cold, damp air of the foggaras lowered the temperature inside the homes that were built over them, resulting in an ancient form of air-conditioning.
The Garamantes who thrived until about 500 CE, when some archaeologists believe they began to deplete she aquifer. As the foggaras supplied less and less water, the Garamantes' population declined, their civilization eventually collapsed. However, at least six hundred of the ancient foggaras survive. The stone mounds that mark their ventilation shafts are still visible in what is now southwestern Libya, where they can be seen even now.
23.
Answer and Explanation
Your Answer is
Correct Answer is B
Explanation
Rather than is a fixed collocation, so A/C/D is excluded.