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Up to four levels of a WBS can be mapped to a business-friendly name. If a particular level of the WBS is not used in your firm, you can deactivate the level using the Activate / Deactivate controls on the right side of the WBS grid. When you map a WBS level to a business-friendly name, that name is displayed as the field name for the various WBS levels when assigning a WBS to a test, sample or activity.
