The correct outcomes are High availability and Fault tolerance.

Elastic Load Balancing continuously monitors instance health and routes traffic only to healthy targets and it distributes incoming requests across multiple Availability Zones which helps the application remain reachable if some instances or an Availability Zone fail and thus provides both High availability and Fault tolerance.

Lower infrastructure cost is not guaranteed because a load balancer is a charged managed service and it does not inherently reduce compute or storage expenses.

Agility is a general cloud advantage and it is not a capability that the load balancer itself directly delivers.

Amazon S3 is an object storage service and it is unrelated to the direct operational benefits that a load balancer provides.

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