What combination of services should the team use to build a custom algorithm in Amazon SageMaker?

Explanations:

AWS Secrets Manager is used for storing and managing secrets such as API keys, passwords, and tokens, but it is not directly involved in building or deploying custom algorithms in SageMaker.

AWS CodeStar is a service that facilitates the development and deployment of applications but does not specifically cater to the requirements of training algorithms in SageMaker. It does not help with storing assets or submitting code.

Amazon ECR (Elastic Container Registry) is a fully managed Docker container registry that allows the team to store, manage, and deploy Docker container images, which is essential for deploying custom training algorithms in SageMaker.

Amazon ECS (Elastic Container Service) is used for running containerized applications but is not required for building or deploying custom algorithms in SageMaker. SageMaker does not rely on ECS for algorithm training.

Amazon S3 (Simple Storage Service) is used for storing the training data and external assets required by the custom algorithm. It provides a durable and scalable storage solution essential for SageMaker training jobs.