Which statement about compression in Autonomous Transaction Processing is correct?

The statement that compression in Autonomous Transaction Processing is enabled by default is accurate. In Oracle Autonomous Database, the technology is designed to optimize performance and efficiency, and part of this optimization includes using compression techniques automatically. This helps reduce the storage footprint and improves query performance without requiring manual configuration from the user.

This default setting simplifies the user experience, allowing users to focus on their business logic and data analysis, rather than on fine-tuning the storage aspects of their database. As a result, even users without deep database management expertise can leverage the benefits of data compression immediately upon setting up their Autonomous Database environment.

As for the other options, compression being required for all tables is not accurate, as there may be scenarios where certain tables do not benefit from compression. The requirement of specific privileges is also not necessary since compression is automatically managed by the Autonomous Database. Lastly, the statement regarding Hybrid Columnar Compression not being supported is misleading; while certain forms of compression might not be explicitly labeled as Hybrid Columnar Compression, Oracle offers various advanced compression techniques that are beneficial in the Autonomous Database.