Which AWS services or tools can report on the quotas so that the company can improve the reliability of the application?

Explanations:

The Service Quotas console provides a comprehensive view of your service limits (quotas) and allows you to request increases for those limits, making it a primary tool for monitoring service quotas.

AWS Trusted Advisor provides recommendations to optimize your AWS infrastructure, including alerts on service limits and quotas that can help improve application reliability during scaling events.

AWS Systems Manager is primarily used for managing and automating operational tasks on AWS resources but does not specifically monitor or report on service quotas.

AWS Shield is a managed DDoS protection service, which does not provide information on service quotas or limits relevant to application usage.

AWS Cost Explorer helps track and manage AWS costs and usage but does not report on service quotas or limits that could affect application reliability during scaling events.