Windows XP mode on a Windows 7 Professional machine fails to load. Which of the following isMOST likely the cause?（）
A、The machine does not have enough processor cores to allow for this feature.
B、Virtualization support is not enabled in the BIOS.
C、A license of Windows XP must be purchased in order to use Windows XP Mode.
D、The machine does not have enough RAM to allow for this feature.
下列关于软件测试的目的和准则的叙述中，正确的是（ ）。
A、软件测试是证明软件没有错误
B、主要目的是发现程序中的错误
C、主要目的是确定程序中错误的位置
D、测试最好由程序员自己来检查自己的程序
AutoCAD中，对象的阵列有哪几种方式（）。
A、环形
B、圆形
C、线形
D、矩形
数据流图用于抽象描述一个软件的逻辑模型，数据流图由一些特定的图符构成。下列图符名标识的图符不属于数据流图合法图符的是（ ）。
A、控制流
B、加工
C、存储文件
D、源和潭
In which case would you use a FULL OUTER JOIN?（）
A、Both tables have NULL values.
B、You want all unmatched data from one table.
C、You want all matched data from both tables.
D、You want all unmatched data from both tables.
E、One of the tables has more data than the other.
F、You want all matched and unmatched data from only one table.
You have performed the first step in placing your database into ARCHIVELOG mode. The second step is deciding whether the online redo log files are to be archived automatically or manually. Which action should you take to enable archiving at instance startup？（）
A、 A
B、 B
C、 C
D、 D