You execute the following command to change the status of the SALES tablespace：  SQL> ALTER TABLESPACE sales OFFLINE；  Which statements describe the effect of the command（）

• A、The tablespace would require recovery to go back online.
• B、A checkpoint is taken on all data files that are associated with the SALES tablespace.
• C、The sessions that subsequently try to access the objects in the SALES tablespace receive an error.
• D、The new status of the SALES tablespace is recorded in the control file when the database instance is closed.