What is an advantage of RAID 6 over RAID 5?

A.
lower cost

B.
higher performance

C.
easier implementation

D.
higher data availability

Explanation:
RAID 6 has additional protection against block failures and controller errors by the extra parity.
http://www.techrepublic.com/blog/the-enterprise-cloud/raid-5-or-raid-6-which-should-you-select/