Which AWS service offers threat detection and continuously monitors for malicious activity and unauthorized behavior in AWS accounts?

Explanations:

Amazon Macie is a data security and privacy service that uses machine learning to discover and protect sensitive data in AWS, primarily focusing on data classification and protection, rather than threat detection in accounts.

AWS Config is a service that provides visibility into the configuration of AWS resources and monitors compliance with policies. It does not specifically focus on threat detection or monitoring for malicious activity.

Amazon GuardDuty is a threat detection service that continuously monitors AWS accounts and workloads for malicious activity and unauthorized behavior. It analyzes data from various sources such as AWS CloudTrail, VPC Flow Logs, and DNS logs to detect potential threats.

Amazon Inspector is a security assessment service that helps improve the security and compliance of applications deployed on AWS. It primarily focuses on identifying vulnerabilities in applications, not on continuous monitoring for threats in AWS accounts.