Department A had 4,100 units in work in process that were 79% completed as to labor and overhead at the beginning of the period, 37,500 units of direct materials were added during the period, 39,300 units were completed during the period; and 2,300 units were 30% completed as to labor and overhead at the end of the period. All materials are added at the beginning of the process. The first-in, first-out method is used to cost inventories. The number of equivalent units of production for material costs for the period was

a.37,500

b.39,300

c.35,200

d.41,600