Refer to the exhibit.

The load balancers should be co-located in area 0 because the design is using the same /32 application address from multiple OSPF-enabled devices. This is an anycast-style design: several load balancers advertise the same host route, and the routing protocol sends clients to the topologically best available instance. In OSPF, route preference is strongly affected by route type. Intra-area routes are preferred over interarea routes, and interarea summarization can also hide useful path details. If identical anycast host routes are originated from different nonbackbone areas, hosts may not always select the closest or most resilient load balancer, and failure behavior can become inconsistent. Placing the load-balancer anycast advertisements in area 0 keeps the routing decision consistent and avoids unnecessary interarea preference complications. Configuring X, Y, and Z as different areas would make the problem worse, and placing only one load balancer in area 0 does not provide uniform resilience. Reference topics: OSPF area design, anycast host routes, intra-area preference, backbone area, application load-balancer resilience.