A Platform App Builder wants to create a report to compare the number of support...

Grouping is the correct reporting capability because the requirement is to compare Case counts across two categorical dimensions: Status and Priority. Salesforce reports support grouping records by rows and columns. The app builder can group Cases by Status and then by Priority, or configure a matrix-style report using one field for row grouping and another for column grouping. The resulting subtotals and grand totals make the comparison immediately visible. Filters determine which records are included but do not organize the resulting records into comparison categories. Bucket columns are useful for creating temporary categories without adding Salesforce fields, but Status and Priority already provide the required categories. A custom report type controls which related objects and fields are available, not how existing Case records are grouped.

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