Explanation:
The ROWID datatype stores information related to the disk location of table rows. They also uniquely identify the rows in your table. The ROWID datatype is stored as a hexadecimal string.
Incorrect Answers:
1: It is not a binary data. The ROWID datatype is a hexadecimal string.
2: It is not a character data. The ROWID datatype is a hexadecimal string.
3: It is not a raw binary data. The ROWID datatype is a hexadecimal string.
4: It is not binary data stored in an external file. The ROWID datatype is a hexadecimal string.
OCP Introduction to Oracle 9i: SQL Exam Guide, Jason Couchman, p. 216
Chapter 5: Creating Oracle Database Objects

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