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问题 单项选择题

下面是关于8259A可编程中断控制器的叙述，其中错误的是：

A． 8259A具有将中断源按优先级排队的功能

B． 8259A具有辨认中断源的功能

C． 8259A具有向CPU提供中断向量的功能

D． 两片8259A级联使用时，可将中断源扩展到16级

答案

参考答案：D

解析：本题考查中断控制方式。PC/XT使用一片8259A管理8级可屏蔽硬件中断， PC/AT及以上的系统使用两片8259A级管理15级可屏蔽硬件中断，而不是16级。 因此选D。

单项选择题

What can be inferred about old nepotism

A．Parents maximized the family advantages for the benefits of their children.

B．Parents gave full respect to the likes and dislikes of their children.

C．Children had their own choice of career and marriage.

D．Children willingly lived on the expectations of their families.
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单项选择题

She’s cute, no question. Symmetrical features, flawless skin, looks to be 22 years old—entering any meat-market bar, a woman lucky enough to have this face would turn enough heads to stir a breeze. But when Victor Johnston points and clicks, the face on his computer screen changes into a state of superheated, crystallized beauty. "You can see it. It’s just so extraordinary," says Johnston, a professor of biopsychology at New Mexico State University who sounds a little in love with his creation.
The transformation from pretty woman to knee-weakening babe is all the more amazing because the changes wrought by Johnston’s software are, objectively speaking, quite subtle. He created the original face by digitally averaging 16 randomly selected female Caucasian faces. The changing program then exaggerated the ways in which female faces differ from male faces, creating, in humanbeauty-science field, a "hyper-female". The eyes grew a bit larger, the nose narrowed slightly and the lips plumped. These are shifts of just a few millimeters, but experiments in this country and Scotland are suggesting that both males and females find "feminized" versions of averaged faces more beautiful.
Johnston hatched this little movie as part of his ongoing study into why human beings find some people attractive and others homely. He may not have any rock-solid answers yet, but he is far from alone in attempting to apply scientific inquiry to so ambiguous a subject. Around the world, researchers are marching into territory formerly staked out by poets and painters to uncover the underpinnings of human attractiveness.
The research results so far are surprising—and humbling. Numerous studies indicate that human beauty may not be simply in the eye of the beholder or an arbitrary cultural artifact. It may be ancient and universal, wrought through ages of evolution that rewarded reproductive winners and killed off losers. If beauty is not truth, it may be health and fertility: Halle Berry’s flawless skin may fascinate moviegoers because, at some deep level, it persuades us that she is parasite-free.
Human attractiveness research is a relatively young and certainly contentious field—the allure of hyper-females, for example, is still hotly debated—but those on its front lines agree on one point: We won’t conquer "looks-ism" until we understand its source. As psychologist Nancy Etcoff puts it: "The idea that beauty is unimportant or a cultural construct is the real beauty myth. We have to understand beauty, or we will always be enslaved by it. \

The word "hatched" underlined in Paragraph 3 is closest in meaning to ______.

A．plot

B．plan

C．scheme

D．engineer
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