Data Presentation 1 (table) for mold-growth prevention test lists humidity: Room A = 9 units; Room B = 11 units; Room C = 12 units; Room D = 6 units. Data Presentation 2 (bar graph) lists surface temperature: Room A = 24 units; Room B = 19 units; Room C = 19 units; Room D = 18 units. Suitability margin equals (humidity - 8.5) + (21.5 - surface temperature). Which sample has the greatest margin?