Answer C is correct. To correct fragmentation of indexes, you need to reorganize the indexes. You could rebuild the indexes to correct fragmentation issues, but you would need to take the data offline. Defragmenting the disk does not correct fragmentation within the data and log files. DBCC CLEANTABLE is used to reclaim space dropped from variable-length and text columns. DBCC CHECKIDENT checks the current identity value for a table.
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