Five Azure VMs run IIS behind an Azure load balancer LB1. To ensure a client is consistently routed to the same server across requests, which configuration is required?

Setting session persistence to "Client IP" (also known as source IP affinity) ensures that requests from the same client IP address are always directed to the same backend VM. This is crucial for maintaining session state in applications like IIS, where a client might store session-specific data on a particular server. Enabling Floating IP (Direct Server Return) is used for specific scenarios like active-passive clusters or network virtual appliances, not for maintaining client session affinity with multiple active servers. Switching the load balancer protocol to UDP is irrelevant for HTTP/HTTPS session persistence, as IIS typically uses TCP. Setting the Idle timeout to 20 minutes only defines how long a TCP connection can remain inactive before being closed by the load balancer; it does not guarantee that subsequent connections from the same client will go to the same server.