Question

select the best evidence to support the statement that there are no plants at the top of mount everest.
mount everest in nepals himalaya mountains is the tallest mountain on earth, almost 5 1/2 - miles (29,029 feet or 8,848 meters) above sea level.
the lower parts of mount everest are covered with plants of birch, fir, and pine trees. as the altitude increases, only dwarf trees or shrubs grow. still higher, you find only lichens and mosses. plants cant develop in snow, so they disappear at the permanent snow line above 18,500 feet (5,639 meters). animals that live up high have furry coats that help them retain body heat. himalayan bears find sheltered caves in which they hibernate in winter months, when food is not easily available. yaks are used as beasts of burden by the sherpas on mount everest.
from seymour simon, seymour simons extreme earth records. copyright 2012 by seymour simon

Explanation:

The text states that plants can't develop in snow, and the permanent snow line is above 18,500 feet. Since the top of Mount Everest is at 29,029 feet (which is above 18,500 feet), there are no plants there.

Answer:

Plants can't develop in snow, so they disappear at the permanent snow line above 18,500 feet (5,639 meters).