To answer this question, you need to understand how Oracle manages storage for database objects.
When a user creates an object (such as a table or index) without specifying a TABLESPACE clause, Oracle will store the segment in the user's default tablespace.
Option A) Default tablespace for the user - This option is correct. When a user does not specify a TABLESPACE clause while creating an object, Oracle will store the segment in the user's default tablespace.
Option B) Oracle will give an error - This option is incorrect. Oracle does not give an error when a user does not specify a TABLESPACE clause. Instead, it uses the default tablespace for the user.
Option C) System tablespace - This option is incorrect. The system tablespace is used for storing system-related objects and metadata, not user-created objects.
Option D) Users tablespace - This option is incorrect. The "USERS" tablespace is a commonly used tablespace for storing user-created objects, but it is not the default tablespace for every user.
The correct answer is A) Default tablespace for the user. This option is correct because Oracle will store the segment in the user's default tablespace if the TABLESPACE clause is not specified during object creation.