Lizana Clinic uses client-visits as its measure of activity. During December, the clinic budgeted for 3,200 client-visits, but its actual level of activity was 3,180 client-visits. The clinic has provided the following data concerning the formulas used in its budgeting and its actual results for December

Data used in budgeting:

	Fixed element per month	Variable element per client-visit
Revenue		$35.20
Wages and salaries	$27,200	$11.20
Expendables	1,200	5.20
Facility expenses	10,200	1.00
Administrative expenses	6,200	0.30
Total expenses	$44,800	$17.70

Actual results for December:

Revenue	$124,670
Wages and salaries	$72,020
Expendables	$22,704
Facility expenses	$14,620
Administrative expenses	$8,125

The activity variance for net operating income in December would be closest to:

A $3,999 U

B $3,999 F

C $350 U

D $350 F