Answer:
The computer has been infected with crypto-malware
Step-by-step explanation:
From the question, we are informed about Ann, a user, reported to the service desk that many files on her computer will not open or the contents are not readable. The service desk technician asked Ann if she encountered any strange messages on boot-up or login, and Ann indicated she did not. In this case, What is MOST likely to occurred on Ann's computer is that the computer has been infected with crypto-malware.Crypto-malware can be regarded as one of the malware threats that very common, and very insidious compare to some malware because it can't be easily detected. It is known as one of the malware that steal data and can hide in background for long mining there