Which public cloud provider requires the creation of subnets that are dedicated to Cloud NGFW...

AWS: Cloud NGFW for AWS leverages AWS Gateway Load Balancer (GWLB) endpoints. These endpoints require dedicated subnets in your VPC for each Availability Zone where you want to deploy the Cloud NGFW. This ensures high availability and proper traffic routing.  

Let's look at why the other options are not the primary answer:

Google Cloud Platform (GCP): While GCP has its own networking constructs, Cloud NGFW for GCP doesn't have the same dedicated subnet requirement for endpoints as AWS.

Alibaba Cloud: I don't have specific information about Cloud NGFW deployment models for Alibaba Cloud.

Microsoft Azure: Cloud NGFW for Azure integrates with Azure Virtual WAN and doesn't have the same dedicated subnet requirement for endpoints as AWS.