Which of these statements about Availability Zones is not true?

The statement identifying that a data center can be used for more than one Availability Zone is not true. In AWS, an Availability Zone is essentially a distinct location within an AWS Region, consisting of one or more data centers. Each of these Availability Zones is designed to be isolated from failures in other Zones to ensure high availability and fault tolerance.

The architecture behind Availability Zones is such that they operate independently of each other, which allows for effective load balancing and disaster recovery strategies. Since an Availability Zone is defined by its physical infrastructure and networking, sharing a data center across multiple Availability Zones would contradict the fundamental design principle of isolation that is intended to protect applications from localized issues, such as power failures or network outages.

When considering the other statements, they accurately reflect the characteristics of Availability Zones. They are indeed comprised of multiple data centers, connected with high-speed private links to facilitate low-latency communication. Additionally, the design of Availability Zones emphasizes fault isolation, allowing businesses to architect their applications in resilient ways, utilizing resources across multiple Zones to mitigate risk.