Examine the command： SQL> ALTER USER skd ACCOUNT LOCK； Which two statements are true after the command is executed（）
- AThe SKD user cannot log in to the database instance.
- BThe objects owned by the SKD user are not accessible to any user.
- CThe other users can access the objects owned by the SKD user， on which they have access.
- DThe password for the SKD user expires and the user is forced to change the password at the next log in.