Answer: Amazon GuardDuty

Amazon GuardDuty is the correct answer (Option A). It is a threat detection service that continuously monitors your AWS accounts and workloads for malicious activity. It uses machine learning and threat intelligence to identify threats such as account compromise, data exfiltration, and suspicious API activity. When a security issue is detected, GuardDuty generates findings and sends alerts to help users take appropriate actions to remediate the threat. The other options provided are for different services: AWS Secrets Manager (Option B) is for managing secrets, Amazon Cognito (Option C) is for user sign-up, sign-in, and access control, and AWS Certificate Manager (Option D) is for SSL/TLS certificate management.

Author: LeetQuiz Editorial Team