AWS Trusted Advisor is correct because it runs Service Limits checks that show when your EC2 usage is approaching current quotas so you can request increases before launching the planned additional instances.

AWS Trusted Advisor compares your resource usage to service quotas and highlights nearing limits while providing links and guidance to request quota increases for EC2 and other services. This proactive guidance is why it is the right tool for assessing whether additional instances will exceed existing quotas.

AWS Health Dashboard is focused on service health and account specific events and it does not monitor service quota usage or warn when you approach limits.

AWS Cost Explorer analyzes spending patterns and forecasts costs and it does not evaluate or report on service quota limits.

Amazon CloudWatch collects metrics logs and alarms for performance and operational health but it does not determine how close your resources are to EC2 service quotas.

Full AWS Practitioner Certification Question