The EMP table has some discrepancy in data entry with a particular employee ID. You execute the query as shown in the Exhibit to retrieve all versions of the row that exist between two SCNs. View the Exhibit. Which two statements about the results of the query shown in the Exhibit are correct?（）

• A、The LAST_SCN value in the first row is NULL, which means that the versions of the row still exist at SCN 6636300. LAST_SCN
• B、The LAST_SCN value in the second row in NULL, which means that the version of the row still exists at SCN 6636300.
• C、The LAST_SCN value in the third row is 6636280, which means that the version of row exists above SCN 6636280.
• D、The LAST_SCN value in the second row is NULL, which means that the version of the row no longer exists because it was deleted. LAST_SCN