Security Doors has a standard variable overhead rate of $4 per direct labour hour. The standard quantity of direct labour per unit of production is 3 hours. The company's static budget was based on 50 000 units. Actual results for the year are as follows: Actual units produced 45 000 Actual direct labour hours 120 000 Actual variable overhead $495 000 What is Security Door's flexible budget for variable overhead costs for the actual output? Select one: A. $540 000 B. $432 000 C. $495 000 D. $600 000