看了新东方的题目解析的答案是D，但是TPO模考软件的答案是B，
两方的解释好像都可以....
想请问各位大大哪个答案是才正确的，以及为什么是这个选项，
感激不尽!!
12、Look at the four squares [ ] that indicate where the following sentence
could be added to the passage.
For this reason, the total amount of plant material in a desert is often 100
times less than the amount of plant material in an equivalent area of
temperate forest.
Where would the sentence best fit?
PARAGRAPH 1 The harsh conditions in deserts are intolerable for most plants
and animals. Despite these conditions, however, many varieties of plants and
animals have adapted to deserts in a number of ways. Most plant tissues die
if their water content falls too low: the nutrients that feed plants are
transmitted by water; water is a raw material in the vital process of
photosynthesis; and water regulates the temperature of a plant by its ability
to absorb heat and because water vapor lost to the atmosphere through the
leaves helps to lower plant temperatures. ■ Water controls the volume of
plant matter produced. ■ The distribution of plants within different areas
of desert is also controlled by water. ■ Some areas, because of their soil
texture, topographical position, or distance from rivers or groundwater, have
virtually no water available to plants, whereas others do. ■