An application receives phone-submitted cell-tower data via Azure Web PubSub, processed by Azure Functions and delivered through a CDN. The Azure Function must be protected against misconfigured or unauthorized invocations. Which HTTP header should you allow through the CDN to support the function protection?

The WebHook-Request-Origin header is used to verify the origin of a webhook request, which is crucial for protecting Azure Functions from unauthorized invocations, especially when integrated with services like Azure Web PubSub. By allowing this header through the CDN, the Azure Function can validate that the request originated from a trusted source, preventing spoofing or unauthorized calls. Authorization is used for authentication credentials, not origin verification. WebHook-Request-Callback specifies a URL for callback, not security. Resource is too generic and doesn't provide specific security context for webhook origins.