Three Scrum Teams work on one product. Team A includes automated regression tests in its Definition of Done, Team B does not. Why does the Scrum Foundations material treat this as a problem?

• AIt is not a problem, since each team may define quality for its own work.
• BTeam B should adopt Team A's Definition of Done because it is stricter.
• CTeams working on the same product must mutually define and comply with the same Definition of Done, otherwise the combined Increment has no consistent meaning and quality depends on which team happened to do the work.
• DThe Product Owner should maintain two separate Product Backlogs so the difference is visible.