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问题 选择题

下列选项中，不属于生物多样性3个基本方面的是

A．生物物种的多样性

B．生物数量的多样性

C．生物遗传的多样性

D．生态系统的多样性

答案

答案：B

题目分析：生物的多样性包含物种多样性，遗传多样性和生态系统多样性，生物物种之间的差异是由各自的遗传物质决定的，生物遗传多样性是物种多样性的基础，任何一种生物都生活在一定的生态环境中，生态系统多样性为不同种类的生物提供了各自的栖息或是生存环境。故选项B不符合题意。

填空题

Happy 75th Birthday, Social Security


1. On its 75th anniversary Social Security is once again under attack and so are its defenders. Those who would axe benefits are spreading myths designed to make you think there is a looming crisis. Well, it is just not true. The stark reality is that it will be several decades before the program encounters any financial problems. The program’s trust fund will have a ＄4.3 trillion surplus by 2023, and can pay all its obligations for decades to come. And strengthening Social Security is easy—making the very rich pay their fair share by lifting the cap on contributions by the wealthy would allow the program to pay all its obligations indefinitely.
2. Social Security was a centerpiece of FDR(Franklin Delano Roosevelt)’s New Deal reforms that helped this country recover from the Great Depression. These programs provided Americans a measure of dignity and hope and lasting security against the vicissitudes of the market and life. FDR therefore accomplished what the venerable New Deal historian David Kennedy says is the challenge now facing President Obama—a rescue from the current economic crisis which will also make us "more resilient to face those future crises that inevitably await us."
3. This anniversary is also a reminder of how major social reforms in this country have come about—in fits and starts. As former Clinton adviser Paul Begala observed in a Washington Post op-ed, "No self-respecting liberal today would support Franklin Roosevelt’s original Social Security Act... If that version of Social Security were introduced today, progressives like me would call it cramped, parsimonious, mean-spirited and even racist. Perhaps it was all those things. But it was also a start. And for 74 years we have built on that start."
4. Indeed when Social Security was first passed it left out African Americans and migrant workers. It was an imperfect piece of legislation but one that progressives built on to create the program we know today—a program like Medicare—that people feel an emotional connection to and will fight to protect. A new campaign from MoveOn and Campaign for America’s Future will tap into that energy, enlisting candidates to pledge their support to Social Security this election season—opposing any cuts in benefits, including raising the retirement age. And these candidates would be wise to pay attention: A just-released poll shows that 65% of voters reject raising the retirement age to 70. And a separate AARP (American Association of Retired Persons) poll shows the vast majority oppose cutting Social Security to reduce the deficit, and 50% of non-retired adults are willing to pay more now in payroll taxes to ensure Social Security will be there when they retire.
5. Progressives can also mark this anniversary by not only rededicating themselves to defending Social Security, but also going on the offensive to expand and improve our social security system to provide economic security for everyone.

A. the candidates of this election
B. the wealthy
C. the financial deficit
D. a system of sustainable security
E. the progressives
F. today’s social security system
G. the ups and downs of the market
To enhance Social Security, everyone should contribute, especially ______.
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选择题

Harry Potter is so interesting a book that lots of teenagers like to read _____. [ ]

A. it

B. this

C. that

D. one

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