The MBR of a hard disk is a collection of boot records that contain disk information such as disk architecture, cluster size, and so on. The main work of the MBR is to locate and run necessary operating system files that are required to run a hard disk. In the context of the operating system, MBR is also known as the boot loader. Which of the following viruses can infect the MBR of a hard disk?

Each correct answer represents a complete solution. Choose two.