Answers A and B are correct. Table partitioning should balance processing against multiple machines or align resources for more appropriate use. Covering indexes will make queries against index elements operate faster. By definition, covering indexes are those created by need, based on the queries being performed. Triggers generally slow performance due to additional processing during operations affecting the trigger. RAID 5 is a disk orientation in which data is written, a calculation is performed, and then a second write occurs. Two writes for every data operation would negatively affect performance. C2 security is complete auditing that could drastically slow performance.
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