The "docker rmi" command removes images, making it the correct answer. The "docker rm" command removes containers. The other commands are invalid and do not exist in Docker syntax.

The "lsusb" command lists connected USB devices, making it the correct answer. The "lscpi" command is used to list all PCI devices. The other options are not valid commands.

The correct answer is "ip route change default via 10.20.30.1 dev eth2". The other "ip route" commands are invalid.

The "docker rm" command removes containers. The "docker rmi" command removes images. The other commands of "docker remove" and "docker del" are not actual commands. Those subcommands of "remove" and "del" are invalid and do not exist in Docker syntax.

The correct answer is "ls [^e]*" as it uses file globbing to exclude files and directories that begin with the letter "e". File globbing allows you to list a character or set of characters in square brackets to match. To negate the matching of the character or characters in the brackets, precede the character(s) with the caret symbol (^). Therefore, "[^e]" matches any character except "e". In file globbing, an asterisk matches zero or more of the preceding characters. Therefore, "[^e]*" matches zero or more of any character except for "e", making it the correct answer.

Standard locations for SSL certificates are "/etc/ssl" and "/etc/pki", making "/etc/pki" the correct choice. "/etc/ssh" is used to store ssh (secure shell) configuration, not SSL configurations or files. The other directories do not exist.

The format of redirecting standard input from a file to a command is: "command < /path/to/file", making "mysql < db_backup.sql" the correct answer. The greater-than sign (>) and double greater-than signs (>>) are used to redirect output from a command. The pipe symbol (|) sends the standard output of the command preceding the pipe symbol to the standard input of the command following the pipe symbol.

The "lvs" command displays information about Logical Volumes, making it the correct answer. The "pvs" command displays information about Physical Volumes. The "vgs" command displays information about Volume Groups. The "logical-volumes" command is invalid.

The "/etc/ssh/sshd_config" file is typically used for SSHD (OpenSSH daemon) configuration. The "/etc/ssh/ssh_config" file is typically used for SSH client configurations. The other files are invalid.

The "-R" option to the "chmod" command changes the mode/permissions on files and directories recursively, making it the correct answer. The remaining options to the "chmod" command are invalid.