47 Which of the following statements about the Qinghai-Tibet Railroad is NOT true according to this passage?
(A) It runs across high altitudes.
(B) It connects Lhasa with Qinghai.
(C) It causes the permafrost to melt.
(D) It marks an amazing engineering victory.

China completed the construction建築物, 建造；建設 of the Qinghai-Tibet西藏 Railroad in 2006.

This 1,142-km railroad line runs across the snow-covered plateau平地, 高原 of Tibet青藏, effectively linking the Tibetan西藏 capital首都, Lhasa, to the northwestern在西北 province of Qinghai.

Also known as the Pan-Himalayan Railroad, this record-breaking railroad rises to 5,072 meters, earning the title as the world's highest passenger train with more than eighty percent of the track 13,000 feet or 3,962 meters above sea level.

The Qinghai-Tibet Railroad is a great engineering achievement.

Since it was built at high altitude海拔, both engineers and workers had to breathe bottled oxygen for fear of altitude海拔 sickness有病的, 患病 while working on the construction建築物, 建造；建設 of the track道路, （鐵路的）軌道.  

additionally另外, there were many other challenges they had to cope with, including the soil泥土，土壤, 國家 that can rise and  sink沈沒 as the season changes.

Some section部分 of track had to be laid（lay的過去式及過去分詞）on ground that is permanently frozen.

Due to global warming, the rising temperatures may cause this permafrost永凍層，永凍土層 melt, making the land sink to a lower level.

The track may become bent彎曲 or curve曲線；轉彎 as a consequence（常指不好或不利的）結果.  

nevertheless不過，仍然；儘管如此, some smart countermeasure對策；反措施 were taken so that the engineers managed to cool off使…感到涼快; 使…變涼 the roadbed by keeping the permafrost永凍層，永凍土層 stable.

The cost savings to travelers resulting from the completion完成；結束；完工 and operation of the Qinghai-Tibet Railroad are tremendous巨大的；極好.  

Compared with typical fare付款, 車費 for direct直接 air travel, a typical train fare between Beijing and Lhasa is much cheaper.

Moreover, travelers get to enjoy the magnificent極好的；壯麗的 sights and scenery along the way, making the long trip more than worthwhile值得的；值得花錢.  

It is hoped that with better linkage聯繫；關聯 to the world, the tourism industry will play an increasingly important role in Tibet's economy.

蓋西藏鐵路到底要怎麼讓永凍土融化啦= =