Which three statements are true about the stages of database startup？（）

A、Data files and redo log files can be renamed at the MOUNT stage.

B、Control files are read at the OPEN stage for the location of data files.

C、Control files are required to bring the database to the NOMOUNT stage.

D、Data files and redo log files are made available to users at the OPEN stage.

E、Data files and online redo log files are checked for consistency while opening the database