TestOut Linux Pro Practice Test

The command that displays the disk quota for a user is indeed "quota -u." This command is specifically designed to provide information about disk usage limits that are set for users. When you run this command, it retrieves and shows the quotas assigned to the specified user or the current user if no user name is provided. The "-u" flag specifies that you want to check user quotas rather than group quotas.

The other commands listed do not serve this purpose. "showquota," for instance, might imply a similar function but is not a standard command commonly found in Unix/Linux systems. "diskquota" is not a recognized command in typical Linux distributions. "df," on the other hand, is used for reporting file system disk space usage, showing how much space is available and used on mounted filesystems but does not relate specifically to user quotas. Thus, "quota -u" is the appropriate command for viewing a user's disk quota.