John is analyzing strange behavior on computers in his network. he believes there is malware on the machines. the symptoms include strange behavior that persists, even if he boots the machine to a linux live cd. what is the most likely cause? a. ransomware
b. boot sector virus
c. rootkit
d. key logger

Boot Sector Virus

Explanation:

A malicious software or malware is an executable line of code, programmed by a cybercriminal for ill intentions. There are many types of malware namely; viruses, rootkit, keylogger, trojan horse etc.

A boot sector virus is a kind of malware that runs before the operating system, affecting the boot sector of the hard disk, so even when a linux live cd is running as the operating system, the virus is still active.