TPO4 deer populations of the puget sound - 英檢

Nearly any kind of plant of the forest understory can be part of a deer's diet.
Where the forest inhibits the growth of grass and other meadow plants, the
black-tailed deer browses on huckleberry, salad, dogwood, and almost any other
shrub or herb. But this is fair-weather feeding. What keeps the black-tailed
deer alive in the harsher seasons of plant decay and dormancy? One compensation
for not hibernating is the built-in urge to migrate. Deer may move from
high-elevation browse areas in summer down to the lowland areas in late fall.
Even with snow on the ground, the high bushy understory is exposed; also snow
and wind bring down leafy branches of cedar, hemlock, red alder, and other
arboreal fodder.

2. It can be inferred from the discussion in paragraph 2 that winter
conditions
○ Cause some deer to hibernate
○ Make food unavailable in the highlands for deer
○ Make it easier for deer to locate understory plants
○Prevent deer from migrating during the winter

答案是C
但我自己的答案是B
冬天氣候較差 對那些沒有冬眠的動物來說 會以遷移倒有食物的地方來渡過冬天
但為什麼答案卻是C呢? (手殘剛剛打成B...)
謝謝大家的回答!

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