The Parameter Store, part of Systems Manager, is the appropriate service for managing configuration data and secrets. It allows storing of parameters as plain text or encrypted data, making it suitable for handling sensitive information. It supports version tracking and notifications on parameter changes, and can be accessed dynamically at runtime. This service also provides granular permissions via IAM for controlling access, and integrates with KMS for encryption, ensuring a high security standard without the need to redeploy applications when configurations change.