Specific requirements for Kubernetes cluster on GCP

Question:
The development team for the supply chain project is ready to start building their new cloud app using a small Kubernetes cluster for the pilot. The cluster should only be available to team members and does not need to be highly available. The developers also need the ability to change the cluster architecture as they deploy new capabilities. How would you implement this?

1. Implement an autopilot cluster in us-central1-a with a default pool and an Ubuntu image
2. Implement an autopilot cluster in us-central1 with an Ubuntu image type
3. Implement a private standard regional cluster in us-central1 with a default pool and container-optimized image type
4. Implement a private standard zonal cluster in us-central1-a with a default pool and an Ubuntu image

Answer:
D - is the correct answer. Standard clusters can be zonal. The default pool provides nodes used by the cluster