After logging in to a Linux system, a user is left in the $/$ root directory. Which of the following are possible causes of this problem?

The user's home directory has not been created or is not mounted.

The user does not have execute permission set on the user's home directory.

The user does not have read or write permission set on the user's home directory.

The user's password has expired.

There is no entry for the user in the $/$etc$/$passwd file.