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（）
- AThe tablespace would require recovery to go back online.
- BA checkpoint is taken on all data files that are associated with the SALES tablespace.
- CThe sessions that subsequently try to access the objects in the SALES tablespace receive an error.
- DThe new status of the SALES tablespace is recorded in the control file when the database instance is closed.