Which AWS service or feature will give the application permission to access required AWS services?

Explanations:

AWS Certificate Manager (ACM) is used for managing SSL/TLS certificates and does not provide permissions for accessing AWS services. It is not related to granting permissions to applications or services.

IAM roles are used to grant permissions to AWS services and resources. By assigning an IAM role to an EC2 instance, the application can access required AWS services, such as Amazon SNS, without embedding AWS credentials in the application code.

AWS Security Hub is a security service that provides a comprehensive view of security alerts and security posture across AWS accounts. It does not manage permissions for accessing AWS services.

Amazon GuardDuty is a threat detection service that continuously monitors for malicious activity and unauthorized behavior. It does not grant permissions to access AWS services and is focused on security monitoring.