Answer: Amazon Aurora

Amazon Aurora provides automated backups by default. Aurora automatically backs up your cluster volume and retains restore data for the duration of the backup retention period (default is 1 day, configurable up to 35 days). **Key points about Aurora automated backups:** - Enabled by default at no additional cost - Backup retention period is configurable from 1 to 35 days - Backups are continuous and incremental - Point-in-time recovery is available within the backup window - Backups are stored in Amazon S3 **Other services comparison:** - **Amazon S3**: Does not provide automated backups by default - users must implement their own backup strategies - **Amazon ElastiCache (Memcached)**: Does not support automated backups (only Redis engine supports backups) - **Amazon EFS**: Requires manual configuration for backup policies using AWS Backup service

Author: Ritesh Yadav