Which AWS service should the company use?

Explanations:

Amazon GuardDuty is a threat detection service that monitors for malicious activity and unauthorized behavior but does not provide comprehensive cost optimization, performance, or security best practices.

AWS Trusted Advisor provides real-time guidance on cost optimization, performance, and security best practices, making it ideal for companies looking to improve in these areas.

AWS Management Console is a web-based interface for managing AWS resources but does not directly provide best practice recommendations.

AWS Systems Manager helps manage and automate operational tasks for AWS resources, but it does not focus on providing best practice recommendations across cost, performance, and security.