Which AWS service requires the company to update and patch the guest operating system?

Explanations:

Amazon DynamoDB is a fully managed NoSQL database service. Users do not need to manage or patch any underlying operating systems, as AWS handles all maintenance tasks related to the service.

Amazon S3 (Simple Storage Service) is an object storage service that is fully managed by AWS. Users do not need to manage or patch any operating systems, as there are no underlying servers for users to manage.

Amazon EC2 (Elastic Compute Cloud) provides resizable compute capacity in the cloud and requires users to manage the guest operating systems. This includes updating and patching the OS, as well as configuring security settings.

Amazon Aurora is a fully managed relational database service. AWS manages the infrastructure, including the underlying operating systems, so users do not need to perform updates or patches on the OS.