Department M had 600 units 60% completed in process at the beginning of June, 6,000 units completed during June, and 700 units 30% completed at the end of June. Using the first-in, first-out method of inventory costing, what was the number of equivalent units of production for conversion costs for the period?

A7,300 units

B5,640 units

C6,700 units

D5,850 units