The ability to automatically generate WAF (Web Application Firewall) policies during application deployment is a characteristic of Infrastructure as Code (IaC). IaC allows infrastructure components—such as firewalls, WAF policies, load balancers, and security groups—to be defined, version-controlled, and deployed programmatically.

According to Security+ SY0-701, IaC enhances DevSecOps workflows by embedding security controls directly into deployment pipelines, ensuring consistent, repeatable, and automated application protection. This reduces human error, eliminates configuration drift, and ensures that every new application instance is deployed with the correct WAF rules already in place.

IoT (B) involves connected devices.

IoC (C) refers to Indicators of Compromise.

IaaS (D) provides cloud infrastructure but does not itself automate security policy generation.

Thus, A: IaC is the correct concept enabling automated WAF policy creation.