单项选择题

Adaptation of Living Things
Certain animals and plants develop characteristics that help them cope with their environment better than others of their kind.This natural biological process is called adaptation. Among the superior characteristics developed through adaptation are those that may help in getting food or shelter, in providing protection, and in producing and protecting, the young. That results in the evolution of more and more organisms that are better fitted to their environments.
Each living thing is adapted to its way of life in a general way, but each is adapted especially to its own distinct class. A plant, for example, depends upon its roots to fix itself firmly and to absorb water and inorganic chemicals. It depends upon its green leaves for using the sun's energy to make food from inorganic chemicals. These are general adaptations, common to most plants. In addition, there are special adaptations that only certain kinds of plants have.
Many animals have adaptations that help them escape from their enemies, Some insects are hidden by their body color or shape, and many look like steal or a little branch. The coats of deer are colored to mix with the surroundings. Many animals have the ability to remain completely still when an enemy is near.
Organisms have a great variety of ways of adapting. 'They may adapt in their structure, function, and genetics; in their development and production of the young; and in other respects. An organism may create its own environment, as do warm-blooded mammals, which have the ,ability to adjust body heat exactly to maintain their ideal temperature' despite changing weather; Usually adaptations are an advantage, but sometimes an organism is so well adapted to a particular, environment that, if conditions change, it finds it difficult or impossible to readapt to the new conditions;
Some plants and animals develop superior characteristics so that they may
A.help others of their kind get food, shelter and other ~things needed.:
B.survive even in extremely severe condition.
C.become better adapted to the' environments than' others of their kind.
D.result in the evolution and production of more intelligent organisms,

A.This
B.
Each
C.
Many
D.
Organisms
E.help
F.:
B.survive
G.
C.become
H.
D.result
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听力原文: Crime has its own cycles,a magazine reported some years ago. Police records show a surprising relation between changes in the season and crime patterns. The pattern of crime has changed very little over a long period of years. Murder reaches its high during July and August,as do other violent attacks. Murder,in addition,is more than seasonal;it is a weekend crime. It is also a nighttime crime: 62 percent of murders are committed between 6 P. m. and 6 a. m. One is most likely to be robbed between 6 P. m. and 2 a. m. on a Saturday night in December,January,or February. Except for one strange statistic,May is the least criminal month of all. Apparently our intellectual season cycles are completely different from our criminal patterns. Professor Huntington made a lot of studies to discover the seasons when people read serious books,attend scientific meetings,and make the highest scores on examinations. In all examples,he found a spring peak and an autumn peak separated by a summer low. On the other hand,Professor Huntington's studies showed that June is the peak month for suicides and for admitting patients to mental hospital. June is also a peak month for marriages! Possibly,high temperature and humidity bring on our strange and surprising summer actions,but police officers are not so sure. “There are,of course,no proof of a relation between humidity and murder”,they say. “Why murder's high time should come in the summer time we really don't know”.(30)A.Different kinds of crimes。B.Increasingly high crime rate in the U.S.C.Seasonal changes in the natural environment.D.The relations between changes in the season and crime patterns.