You are a Database Administrator with WonderWeb. You use a password file to establish connections to the Sales database located on the server. You created the password file using the following command：       
ORAPWD file=d：\oracle\ora9i\orapwU01 password=admin entries=4  
You erroneously deleted the password file while the database was running. You re-create the password file using the following command：  
ORAPWD file=d：\oracle\ora9i\orapwU01 password=change_on_install entries=4  
However， when you try to connect as the SYS user， you receive the following error：       
ORA-01031： insufficient privileges  
What should you do to resolve this error？（）

A. Delete the newly created password file and re-create another password file with the password admin， without shutting down the database.
B. Enable the operating system authentication， shut down the database， disable the operating system authentication， and restart the database using the password file.
C. Enable the operating system authentication， shut down the database， re-create the password file using the same ORAPWD command， and restart the database using the password file.
D. Delete the newly created password file， enable operating system authentication and shut down the database. Then， re-create another password file using the same ORAPWD command and restart the database using this password file.