6. Ibsen Clinic uses client-visits as its measure of activity. During December, the clinic budgeted for 3,300 client-visits, but its actual level of activity was 3,340 client-visits. The clinic has provided the following data concerming the formulas used in its budgeting and its actual results for December: Data used in budgeting Fixed Element Variable element per Month per client-visit S 40.00 Revenue S 13.40 4.80 2.10 0.40 S 20.70 Personnel expenses Medical supplies Occupancy expenses Administrative expenses Total expenses S 32,400 1,500 9,100 6,700 S 49,700 Actual results for December Revenue Personnel expenses Medical supplies Occupancy expenses Administrative expenses S 134,170 S 80,776 S 17,302 S 15,754 S 8,296 The net operating income in the flexible budget for December would be closest to: A) $ 13,990 B) S14,762 C) S11,898 D) S12,188