Dermody Snow Removal's cost formula for its vehicle operating cost is $$2,990$ per month plus $$329$ per snow$-$day. For the month of December, the company planned for activity of $23$ snow$-$days, but the actual level of activity was $21$ snow$-$days. The actual vehicle operating cost for the month was $$10,860.$ The spending variance for vehicle operating cost in December would be closest to:a$.$ $$961$ UO b$.$ $$961$ F$0$c$.5303$U d$.$ $$303$ F