Workday report filters allow prompts so users can enter values when running a report. If the prompt value is left blank, Workday treats it as though no filter condition has been applied, so the system returns all available Worker instances regardless of the Location field.

From the Workday Reporting guide:

''Prompts -- You can further narrow and refine your report results by having the user complete prompt fields before they run the report. You can set default values for prompts... If left blank, the filter condition is ignored and all data is returned.''

Therefore, the correct answer is D. All Worker instances, regardless of the value of the Location field.