Explanation:
By executing this query you will extract data from the HR table in your own schema, it will not work with HR synonym for the HUMAN_RESOURCES table of the GENERAL schema.
Incorrect Answers:
1: The results will be retrieved from the table in your own schema, not from the GENERAL schema, using synonym HR.
3: There is no error: data from the table in your own schema will be retrieved by this query.
4: This query will not generate Cartesian product from both tables.
5: This query will not retrieve data from both tables as a FULL JOIN.
OCP Introduction to Oracle 9i: SQL Exam Guide, Jason Couchman, p. 331-335
Chapter 7: Creating Other Database Objects in Oracle

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