The file owner is the user who can change the file attributes and grant access to the file.
In most operating systems, the file owner is the user who created the file or who has been assigned ownership of the file. As the owner of a file, the user has the ability to change the file's attributes, such as its name, location, and permissions.
The file owner also has the ability to grant access to the file to other users on the system. This may involve setting the file's permissions to allow read, write, or execute access to specific users or groups.
Therefore, option B (the user who can change the file attributes and grant access to the file) is the correct answer. Options A and C are incorrect, as the file owner does have the ability to change the file attributes and grant access to the file. Option D is also incorrect, as the file owner is not the only user who can execute the file. Other users with the appropriate permissions may also be able to execute the file.