An administrator finds that all user workstations and servers are displaying a message that is associated with files containing an extension of .ryk. Which of the following types of infections is present on the systems?

The presence of files with an unusual extension like ".ryk" and a message displayed on all systems strongly indicates a ransomware infection. Ransomware encrypts a victim's files and demands a ransom, often displaying a message with instructions and changing file extensions to denote encryption. A virus typically replicates and spreads, often corrupting files or system functions, but doesn't usually display a ransom message or change file extensions globally for a ransom. A Trojan disguises itself as legitimate software to gain access, but its primary goal isn't typically file encryption and ransom demands. Spyware monitors user activity and collects data without consent, but it doesn't encrypt files or display ransom messages.