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A company just starting its business made the following four inventory purchases in June: Date Units Total purchase price June 1 150 units 2,600 June 10 200 units 3,900 June 15 200 units 4,200 June 28 150 units 3,300 14,000 A physical count of the inventory on June 30 reveals that there are 100 units on hand. The inventory method which results in the highest gross profit for June is: A) the FIFO method B) all inventory methods result in the same gross profit C) the LIFO method D) the average-cost method