Jannette Has Been Experiencing Slow Performance on Her Computer

Jannette has been experiencing slow performance on her computer. Today she received an error message saying that an update to her antivirus program failed. When she checked the update history, she discovered that the program had not been updated for two weeks. She restarted her computer and noticed that a file she was working on was no longer available. She also noticed that the network connection was sending data, even when she was not connected to the Internet. ​
What should Jannette do first on her computer?

A) Run anti-malware program.
B) Roll back to a previous date.
C) Quarantine the system.
D) Remediate the infected system.