Server clusters are highly scalable. As demand and load grow, which of the following methods can be used to increase cluster performance?

Server clusters are highly scalable. As demand and load grow, which of the following methods can be used to increase cluster performance?
A . Increase the network bandwidth in the cluster
B . Increase the memory capacity of a single server in the cluster
C . Add a new cluster server to the cluster system
D . Replace the hard disk of a single server in the cluster with a high IO solid-state drive

Answer: C