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阅读下列短文，从每题所给的四个选项（AB、C和D）中，选出最佳选项。It' s never a real problem for us when the weather gets cold． We have many different was of coping with the cold．We can put on more clothes, stay next to a fireplace, turn on the air conditioner or simply travel to a warmer city to spend the winter．But things are not as easy for plantsnlike humans, plants can’t move to escape the cold or generate heat to keep themselves warm．So how do they manageurvive the freezing winter? The cold is a big challenge for plants．Teir living tissues can be damaged when they freeze．t's like a plant's equivalent(相等物）frostbite（冻疮）．Also，the pcess of freezing and thawing（解冻）can causer bubbles to form in the plant's water transport system．f enough of these air bubbles come together as water thaws they can block the flow of water from the roots to the leaves and kill the plant． To live through cold weather，plants have develop three strategies，Se plants，ch as oak trees, avoid freezing damage by dropping their leaves, before the winter chill sets in-effectively shutting off the flow of water between roots and leaves—and growing new leaves and water transport cells when the warm spring returns. Other plants, pine trees for example, protect them-selves by narrowing their water transport cells, which makes it easier for cells to travel among air bubbles．The third stratef;yi8 also the most extreme．Some plant; die on the ground in winter and start growing as new plants from seeds when conditions get warmer． | 
