多项选择题 Which of the following Windows versions includes Windows Defender, by default?（）

单项选择题 A technician is trying to install a previous-generation expansion card into their new laptop.However, the card refuses to fit into the expansion slot. Which of the following is MOST likely the reason?（）

单项选择题 A user’s OS has become corrupt, and the user would like to restore the PC back to when they first bought the machine. Which of the following would be the BEST choice?（）