在教育宗旨问题上，梁启超主张通过教育培养

A．政治家B．学术人才

C．新国民D．实业人才

请在（50）处填上最佳答案

颜色视觉的三个基本属性是

A．色调、波长、照度 B色调、明度、照度

C．波长、明度、饱和度 D．色调、明度、饱和度

从2006年1月1日起，我国废止《农业税条例》，这是具有划时代的历史事件，它有利于：（ ）

A．促进城乡税制的统一

B．推进工业反哺农业，城市支持农村

C．逐步消除城乡差别，推进城乡统筹发展

D．增强农民收入，提高消费水平

Passage Four

Most people do not think of fishes and other sea animals as having voices, and of those who are aware of the fact that many of them can "speak", few understand that these "conversations" have significance. Actually, their talk may be as meaningful as much of our own. For example, some sea animals use their "voices" to locate their food in the ocean expanses (广阔的区域); others use their "voices" to let their fellows know of their locations; and still others, as a means of obtaining mates. Sometimes, "speaking" may even mean the difference between life and death to a sea animal. It appears in some cases that when a predator (食肉动物) approaches, the prey (被捕的动物) depends on no more than the sounds it makes to escape.

Fish sounds are important to man, also. By listening to them, he can learn a great deal about he habits of creatures that make them, the size of the School they form, the patterns of their migrations, and the nature of the environments in which they live. He can also apply this nformation to the more effective utilization of the listening spots he has set up to detect enemy submarines (潜水艇). A knowledge of fish sounds can avoid confusion and unneeded effort when a "new" sound is picked up and the sound sentry (哨兵) must decide whether or not to call an alarm.

46. Among the people who know that many sea animals have voices, few ______.

A. know the meaning of their conversations

B. realize that they can communicate with each other

C. realize that they can make speeches

D. could understand their conversations