In Kali Linux or any Linux system, the chown command is used to change the ownership of files or directories.

Explanation of the options provided:

• chown: This is the command itself, short for "change owner".
• root: This specifies the new owner of the file (file.txt). In this case, it sets the owner to the user-named root.
• root: This specifies the new group owner of the file (file.txt). In this case, it sets the group owner to the group named root.
  Therefore, the command chown root:root file.txt does the following:

Changes the file's owner to root.
Changes the file's group ownership to root.

It changes both the file's owner and group ownership to root.
So, the correct option is: Change both the file's owner and group ownership to root