According to the AWS Shared Responsibility Model:

• AWS is responsible for security OF the cloud - This includes securing the infrastructure, physical security of data centers, edge locations, and hardware security.
• Customer is responsible for security IN the cloud - This includes managing IAM users and permissions, securing application-level access, and configuring security groups.

Option A (Correct): Managing IAM is the customer's responsibility as it involves controlling user access to AWS resources.

Option B: Securing edge locations is AWS's responsibility as part of their infrastructure security.

Option C: Monitoring physical device security is AWS's responsibility in their data centers.

Option D: Implementing SOC standards is primarily AWS's responsibility for their compliance certifications, though customers must implement proper controls within their applications.