Greater ability to scale resources automatically is the correct answer.

A platform managed database gives a bookseller a Greater ability to scale resources automatically because the cloud provider manages the underlying infrastructure and offers built in autoscaling features. This means storage can grow without manual reconfiguration and some managed databases can adjust capacity to match load so the application stays responsive during traffic spikes.

For example Google Cloud managed databases include automatic storage increases for Cloud SQL and horizontal scaling capabilities in Cloud Spanner which let an organization expand capacity with less manual intervention and less operational friction.

Higher total cost of ownership is incorrect because moving to a managed service usually reduces operational overhead and staffing costs even if the listed service fees seem higher. Total cost of ownership often falls when you factor in reduced maintenance time and fewer infrastructure management tasks.

Larger day to day administration workload is incorrect because a PaaS reduces routine administration by handling provisioning, patching, and many operational tasks. The bookseller would generally have a smaller day to day operational burden compared with hosting databases on site.

Removes the need to manage backups and updates entirely is incorrect because managed services do not eliminate responsibility for backups and updates. Providers perform automated backups and offer update mechanisms, but the customer still must configure retention, verify restores, choose maintenance windows, and test upgrades and recovery procedures.

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