A partial planning budget and actual results from Market Works Corp. are given below: Planning Actual u = 1,200 units u = 1,250 units h = 800 hours h=820 hours Sales ($50u) Wages ($12h) Supplies ($0.30u) Maintenance ($400 + $2h) $60,000 $9,600 $360 Sales $64,000 Wages $10,200 Supplies $350 Maintenance $2,400 $2,000 What is the activity variance for Sales? O A. $2,500 favorable B. $4,000 favorable C. $1,500 unfavorable D. $1,500 favorable