The standard Oracle Autonomous AI Database Serverless resource-allocation interface permits the administrator to configure the base compute allocation up to 512 ECPUs using the ECPU slider. This value represents the configured base ECPU count for a single database instance rather than the potential temporary compute consumption obtainable through compute auto scaling.

Oracle distinguishes configured ECPUs from auto-scaled usage. For eligible Autonomous AI Database configurations, compute auto scaling can allow the database to consume additional processing capacity above the configured base according to workload demand. For example, a database configured with 512 ECPUs may be capable of consuming substantially more effective processing capacity when auto scaling is enabled, subject to the service and licensing model.

The 1024-ECPU option therefore does not represent the normal single-instance slider ceiling addressed by this question. The 256- and 128-ECPU values are valid intermediate configurations but are below the maximum.

Consequently, A. 512 ECPUs is correct.

Study Guide reference: Provision and operate Oracle AI Database@Azure Resources — Autonomous AI Database Serverless provisioning, ECPU configuration and compute scaling.

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