You started a long transaction. Before committing， you executed a query on one of the tables currently being modified. You received the following error：  ORA-01555： snapshot too old  How would you prevent such an error in the future？（）

• A、guarantee undo retention
• B、add one more redo log group
• C、size the redo log files appropriately
• D、size the UNDO tablespace appropriately
• E、size the SYSTEM tablespace appropriately
• F、configure an appropriate undo retention interval
• G、change automatic undo management to manual