What should you create?

You have a server named Server 1 that runs Windows Server 2012.
You connect three new hard disks to Server 1.
You need to create a storage space that contains the three disks. The solution must meet the following
requirements:
Provide fault tolerance if a single disk fails.
Maximize the amount of useable storage space.
What should you create?

A.
A spanned volume

B.
A simple space

C.
A parity space

D.
A mirrored space

Explanation:
simple space does not provide fault tolerance, neither does spanned volumes, whereas parity & mirrored
spaces do.
=> so the question is parity space or mirrored space to maximize the amount of useable storage space?
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http://en.wikipedia.org/wiki/Spanned_volume
Unlike RAID, spanned volumes have no fault-tolerance, so if any disk fails, the data on the whole volume
could be lost.
============
http://arstechnica.com/information-technology/2012/10/storage-spaces-explained-a-great-feature-when-it-works/
Storage Spaces explained: a great feature, when it works
Three-way mirroring gives you less usable space than two-way mirroring, but can tolerate the failure of up to
two disks at once.
Parity mirroring gives more usable space than either mirroring mode(a 20GB storage space configured
with two-way mirroring will require about 40GB of physical disk space, but a 20GB parity storage spacerequires
only about 30GB) but comes with the aforementioned performance hit.
==============
http://technet.microsoft.com/en-us/library/jj822938.aspx
NB : Parity spaces are not supported in a failover cluster configuration.