How many additional copies of data are written into the Isilon cluster using HDFS?

A four-node Isilon cluster is being used in a Hadoop workflow with a parity protection of N+2:1. The HDFS protocol has been enabled and is being used to access data.

How many additional copies of data are written into the Isilon cluster using HDFS?
A . None
B . One
C . Three
D . Two

Answer: A