* "100% increase in the throughput of the API" might look correct, as the number of requests processed per second might increase, but is it guaranteed to increase by 100%? Using 4 nodes will definitely increase throughput of system. But it is cant be precisely said if there would be 100% increase in throughput as it depends on many other factors. Also it is nowhere mentioned in the description that all nodes have same CPU/memory assigned. The question is about the guaranteed behavior * Increasing number of nodes will have no impact on response time as we are scaling application horizontally and not vertically. Similarly there is no change in JVM heap memory usage. * So Correct answer is 50% reduction in the number of requests being received by each node This is because of the two reasons. 1) API is mentioned as stateless 2) Load Balancer is used