Explanation: Cross-zone load balancing is always enabled for an Application Load Balancer and is disabled bydefault for a Classic Load Balancer. If cross-zone load balancing is enabled, the load balancerdistributes traffic evenly across all registered instances in all enabled Availability Zones. If cross-zoneload balancing is disabled, the load balancer distributes traffic evenly across all enabled AvailabilityZones. For example, suppose that you have 10 instances in Availability Zone us-west-2a and 2instances in us-west-2b. If cross-zone load balancing is disabled, the requests are distributed evenlybetween us-west-2a and us-west-2b. As a result, the 2 instances in us-west-2b serve the same amount of traffic as the 10 instances in us-west-2a. However, if cross-zone load balancing is enabled,the load balancer distributes incoming requests evenly across all 12 instances. http://docs.aws.amazon.com/elasticloadbalancing/latest/userguide/how-elastic-load-balancingworks.html