The verified answer is C. Amazon Inspector. The company needs automated vulnerability assessment for Amazon EC2-based infrastructure. AWS documentation states that Amazon Inspector scans EC2 instances for package vulnerabilities and network reachability issues and produces findings. It compares instance metadata against vulnerability intelligence and security advisory rules. This is exactly the service used to assess EC2 infrastructure before deploying sensitive workloads such as generative AI models.

AWS also documents that Amazon Inspector scans EC2 instances for common vulnerabilities and exposures, operating system package vulnerabilities, programming language package vulnerabilities, network exposure issues, and network reachability issues. This confirms that Inspector is the correct service for automated vulnerability assessment of EC2-based ML infrastructure.

AWS CloudFormation is incorrect because it provisions infrastructure as code. It can create EC2 instances, security groups, and related resources, but it does not perform vulnerability assessment. Amazon Comprehend is incorrect because it is a natural language processing service used to extract insights from text. It does not scan infrastructure. AWS Trusted Advisor is incorrect because it provides best-practice recommendations across categories such as cost optimization, security, performance, and service limits, but it is not the dedicated automated vulnerability assessment service for EC2 instances.

The requirement is specific: scan EC2-based ML infrastructure for vulnerabilities before deployment. The AWS-native service that performs this function is Amazon Inspector.