You are in the process of configuring a RAID array which will require a hot spare and you ask the Certkiller administrator which of the following RAID technologies implementations will meet your requirement?

A.
RAID 0+5

B.
RAID 3

C.
RAID 2

D.
RAID 0

Explanation:
The RAID 0+5 implementation is used to form large arrays by combining the block striping and parity features of RAID 5 with the straight block striping of RAID 0.
Incorrect
Answers:
B: The RAID 3 specification is designed to use parallel transfers similar to RAID 2, along with byte-level parity striping.

C: The RAID 2 implementation uses data striping with error recovery, and is designed for use where high data-transfer rates are required.
D: RAID 0 is the simplest level, and uses disk striping without parity thus it requires less time for disk access, but no redundancy or error correction is provided making this type of RAID solution only to be used when reliability is not vital.
Reference:
Charles J. Brooks, Server+ Certification Exam Cram 2 (Exam SK0-002), QUE Publishing, Indianapolis, 2006, pp. 192