Final answer:
The Linux utility used to view failed authentication attempts is 'faillog', which provides records and management capabilities for user login attempts. Other options mentioned don't exist in Linux for this purpose.
Step-by-step explanation:
The utility in Linux to view a list of users' failed authentication attempts is faillog. This command displays the faillog record or sets the failure limits for user login attempts. The faillog command can show the number of failed login attempts user has made and can be helpful in monitoring and managing user authentication security. The other options listed, such as badlog, wronglog, and killlog, are not actual commands in Linux for checking failed authentication attempts.
The correct utility to view a list of users' failed authentication attempts in Linux is faillog. Faillog is a command-line utility that displays information about the last login failures for a given user or all users. It provides details such as login attempts, the date and time of the last failed login, and the number of incorrect password entries made by a user.