If you create your database using Oracle Managed Files （OMF）， what is true？（）

• A、You must use Oracle predefined names to identify raw partitions that will hold OMF structures. 
• B、You must define directories for two online redo log groups and three copies of the control file. 
• C、If your CREATE DATABASE command fails, any OMF database files that have already been created will be dropped automatically. 
• D、You must use only OMF data files when adding new tablespaces or data files to your database in the future.