Explanation:
Index EMP_INDX will be created in Scott's default table space by default in Oracle8i.
Incorrect Answers:

1: It's only possible if Scott has SYSTEM table space as default table space, but question does not mention about this fact.
3: Index will be created in Scott's default table space, not in RBS table space.
4: Index will be created in Scott's default table space, not in the same table space as the EMPLOYEE table uses.
Oracle 8, DBA Certification Exam Guide, Jason S. Couchman, p. 917-918. Chapter 19: Tuning Disk utilization

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