Answer D is correct. Generate online recommendations where possible is the only option that is completely non-limiting in its results; its downfall is that it may provide online implementations where they may be more quickly implemented offline. Using the option All recommendations are offline does not limit any of the indexing recommendations, but it also provides no information about items that could be implemented online. Evaluate utilization of existing PDS only does not evaluate anything other than what already exists, ignoring possible improvements of indexes that could be added. Keep all existing PDS does not evaluate the potential gain in eliminating some of the existing indexes. Generate only online recommendations ignores options that could be eliminated offline.
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