The correct responsibilities under the shared responsibility model are Configuring network ACLs, security groups, and host-based firewalls and Enabling server-side encryption for an Amazon S3 bucket.

Customers are responsible for Configuring network ACLs, security groups, and host-based firewalls because network controls and host level security belong to security in the cloud. Customers must design and implement their own ingress and egress rules and any host based firewall rules that protect their instances.

Customers must also take responsibility for Enabling server-side encryption for an Amazon S3 bucket when they want objects encrypted at rest and they must choose and configure the encryption option that meets their requirements. AWS provides encryption features and key management services but the customer configures and enables those options for their data.

Applying database engine patches for Amazon RDS instances is not a customer responsibility for the managed RDS service because AWS applies engine patches and updates as part of the managed offering although customers can control maintenance windows and patching options.

Managing physical security at AWS data center locations is owned by AWS since physical facilities and hardware are part of security of the cloud.

Ensuring compute capacity availability across AWS infrastructure refers to the underlying infrastructure which AWS operates and maintains so AWS is responsible for that capacity while customers plan and request capacity for their own accounts and use scaling features.

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