下列叙述中正确的是
A．数据的逻辑结构与存储结构必定一一对应
B．由于计算机存储空间是向量式的存储结构，因此，数据的存储结构一定是线性结构
C．程序设计语言中的数组一般是顺序存储结构，因此，利用数组只能处理线性结构
D．以上三种说法都不对
参考答案：D
解析： 一种数据的逻辑结构根据需要可以表示成多种存储结构，因此，数据的逻辑结构与存储结构不一定是一一对应的，因此选项A错误。
计算机的存储空间是向量式的存储结构，但一种数据的逻辑结构根据需要可以表示成多种存储结构，如线性链表是线性表的链式存储结构，数据的存储结构不一定是线性结构，因此选项B错误。
数组一般是顺序存储结构，但利用数组也能处理非线性结构。选项C错误。
只有选项D的说法正确。
Read the following passage．Complete the diagram by using the information for the passage． Write NO MORE THAN 3 WORDS for each answer. United Nations officials say now fewer people than they thought are infected with the AIDS virus. Last year, the agency known as UNAIDS thought that 39.5 million people were living with HIV．On Tuesday it reduced by 16% to a little more than 33 million. Agency officials say the low number reflects better information form more countries．The agency reduced the number for five African countries: Angola, Kenya, Mozambique, Nigeria and Zimbabwe. Also, UNAIDS says it now believes the number of new HIV cases per year reached a high in the late 1990s at more than three million．This year, it thinks that 2.5 million people became infected, and 2 million people died of AIDS. Luckily, better treatments are saving lives, and m  ore people are getting the drugs.Yet even as the number of new infections has dropped, UN officials say AIDS is still one of the leading causes of the death worldwide, and the major cause in Africa．African death rates remain high, they say, because treatment needs are not being met．Sub-Saharan Africa had almost 70% of the new cases of HIV reported this year．UNAIDS officials say this is a sharp reduction since 2001, but there is a need to further improve research method. Billions of dollars are being spent preventing and treating HIV．Experts worry that the new number may le  ad to a drop in financial support．But UNAIDS officials say they do not change the need for immediate action and more money．They warn that in some countries, infection rates that were falling are rising again now．Title: A New Report on (71) Infections
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