The correct answer is: C. wall
The wall
command is used to send a message to all users who are currently logged in to the system. The message is displayed on the user’s
The write
command is used to send a message to a single user. The message is displayed in a separate window, and the user can choose to read it or not.
The mail
command is used to send an email message to a user. The message is sent to the user’s email address, and they will receive it in their email client.
The mesg
command is used to control whether or not a user is allowed to receive messages from other users. The mesg y
command allows messages, while the mesg n
command disallows them.
E. None of the above is not a valid option.