Which of the following concepts allows an organization to group large numbers of servers together
in order to deliver a common service?

A.
Clustering

B.
RAID

C.
Backup Redundancy

D.
Cold site

Explanation:
Anytime you connect multiple computers to work/act together as a single server, it is known as
clustering. Clustered systems utilize parallel processing (improving performance and availability)
and add redundancy (but also add costs).
Clustering is done whenever you connect multiple computers to work and act together as a single
server. It is meant to utilize parallel processing and can also add to redundancy.