aws new database in AWS where the customer assumes the responsibility and management of the guest operating system, including updates and security patches. Which of the following services should the customer use code example

Example: responsibility with aws

Amazon Web Services (AWS) is a secure cloud services platform,
offering compute power, database storage and it helps Running 
web and application servers 
in the cloud to host dynamic websites.

in my company We use; 

EC2: 
   - for Running application for different environments(Test, Dev enviroments).
   - and also for Running Jenkins or any other application for testing purpose.
   - and to Run load testing on the application.
We also use S3 (Simple Storage Service):
  - It is Used for file storage, test data storage.
  - It Can be used for part of data processing workflow.
  - and also it Can also be used as code repository.

IAM (Identity and Access Management) is a web service that helps you 
securely control access to AWS resources. You use IAM to control who is 
authenticated (signed in) and authorized (has permissions) to use resources.
   - I use IAM for Permission control of users, applications, typically 
   not configured by application team but by a cloud team.
RDS (Create a sample Postgresql database and connect using Dbeaver):
   - is Used for database, launch database for different environments to 
   support the application.
Lambda:
   - Serverless service that can provide quick and easy solution to run 
   your code without the involvement of EC2.
   - Typically used for data processing incoming files.