Explanation:
ORACLE_LOADER is the default access driver for external tables.
Incorrect Answers:
1: Import is not the default access driver for external tables.
3: Metadata API is not used to convert the data as an access driver.
4: External tables are not processed with direct path export.
Reference:
OCP Oracle9i Database: New Features for Administrators, Daniel Benjamin, p. 131-134
Chapter 3: Manageability Enhancements
Oracle 9i New Features, Robert Freeman, p. 111-116
Chapter 4: New Oracle9i Database DDS and Data-Warehouse Features

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