Azure Fundamentals AZ-900 Practice Test 1

Explanation:
Availability zones expand the level of control you have to maintain the availability of the applications and data on your VMs. An Availability Zone is a physicallyseparate zone, within an Azure region. There are three Availability Zones per supported Azure region.
Each Availability Zone has a distinct power source, network, and cooling. By architecting your solutions to use replicated VMs in zones, you can protect your appsand data from the loss of a datacenter. If one zone is compromised, then replicated apps and data are instantly available in another zone.
Reference:
https://docs.microsoft.com/en-us/azure/virtual-machine-scale-sets/availability