A Dolutegravir is an effective therapy which can also reduce the chance of mutation. B Levels of drug resistance against efavirenz and nevirapine are acceptable and can be controlled. C The same HIV medicines cannot be applied to the rest of the population in other regions. D Efavirenz and nevirapine are crucial components of anti-HIV drugs.

A Authorities try to find effective and tolerable therapies to treat HIV. B Authorities have discovered the causes of resistance to crucial HIV drugs. C WHO conducted surveys to examine the levels of resistance in people who had started HIV treatment. D Authorities have uncovered an alarming surge in resistance to crucial HIV drugs.

A To show that people care more and more about this issue. B To raise readers’ awareness of the importance of the issue. C To stimulate readers’ thinking and relate them to the issue. D To emphasize that the questions are very difficult to answer.

A In studied on honesty by testing whether people would return others’ wallets. B It mainly studied those rich and educated people in the west of the world. C They collected data among different kinds of people around the world. D It was done through experiments in labs instead of real-life situations. E

A People in less developed countries are more likely to keep others’ wallets. B People in higher economic statues are more honest. C The more money out in the wallet, the better we can know people’s honesty. D With greater temptation, comes greater honesty.

A People who lose wallets in Asia and Africa are more likely to find them. B Economists can make much better prediction than people in the street. C It is more likely to return a lost wallet with a larger sum money in. D Men are less likely to return a lost wallet than women.

A The real and universal ones that happen often in our lives. B People do good things to those who they will never meet. C The inner motivation to do the right thing to others. D The altruism that evolved from human development.

A 含有纯虚函数的类不能被声明对象，这些类被称为抽象类 B 继承抽象类的派生类可以被声明对象，但要在派生类中完全实现基类中所有的纯虚函数 C 继承抽象类的派生类可以被声明对象，不需要实现基类中全部纯虚函数，只需要实现在派生类中用到的纯虚函数 D 虚函数和纯虚函数是一样的，没什么区别

A 插入排序在最坏情况下需要O(n 2 )时间 B 插入排序在最佳情况可在O(n)时间内完成 C 插入排序平均需要O(nlog 2n)时间 D 插入排序的空间复杂度为O(1)

A 不可重复读 B 丢失修改 C 读脏数据 D 数据库文件损坏