A security administrator is analyzing a user report in which the computer exhibits odd networkrelated outages. The administrator, however, does not see any suspicious process running. A prior technicians notes indicate the machine has been remediated twice, but the system still exhibits odd behavior. Files were deleted from the system recently. Which of the following is the MOST likely cause of this behavior?

A. Crypto-malware

B. Rootkit

C. Logic bomb

D. Session hijacking