After performing a clean shut down of the database instance for maintenance, you mount the database and then execute a command to open the database:
SQL> ALTER DATABASE OPEN;
Which two statements are true? (Choose two.)
A.
The online redo log files and online data files are opened
B.
All the online data files headers are checked for consistency
C.
Instance recovery is performed before opening the database
D.
The path and existence of all the log file members are checked