While designing your database， you have created the EMPLOYEES table as an index/x7forganized table （IOT）. You want to create a bitmap index on the JOB_ID column to make queries faster. Which task must have been completed so that you are able to create the bitmap index？（）

• A、A primary key must have been created.
• B、A mapping table must have been created.
• C、An overflow tablespace must have been specified.
• D、The PCTTHRESHOLD option must have been specified.