詢問TPO1 插入句題型 第13題 - 英檢

Above the tree line there is a zone that is generally called alpine tundra.
Immediately adjacent to the timberline, the tundra consists of a fairly
complete cover of low-lying shrubs, herbs, and grasses, while higher up the
number and diversity of species decrease until there is much bare ground with
occasional mosses and linchens and some prostrate cushion plants. Some plants
can even survive in favorable microhabitats above the snow line. The highest
plants in the world occur at around 6,100 meters on Makalu in the Himalayas.
@@@ At this great height, rocks, warmed by the sun, melt small snowdrifts. @@@


要插入的句子
This explains how, for example, alpine cushion plants have been found growing
at an altitide of 6,180 meters.

兩個@@@都是選項
一個是正確答案 一個是我的錯誤選擇







正確答案是後者
我選了前者
請問是否有高人可解答?
感謝~~

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