You have deployed a proof-of-concept application by manually placing instances in a single Compute Engine zone. You are now moving the application to production, so you need to increase your application availability and ensure it can autoscale.
How should you provision your instances?

A. Create a single managed instance group, specify the desired region, and select Multiple zones for the location. B. Create a managed instance group for each region, select Single zone for the location, and manually distribute instances across the zones in that region. C. Create an unmanaged instance group in a single zone, and then create an HTTP load balancer for the instance group. D. Create an unmanaged instance group for each zone, and manually distribute the instances across the desired zones.