X-Beams Inc. owned 70% of the voting common stock of Kent Corp. During 2013, Kent made several sales of inventory to X-Beams. The total selling price was $180,000 and the cost was $100,000. At the end of the year, 20% of the goods were still in X-Beams' inventory. Kent's reported net income was $300,000. What was the non-controlling interest in Kent's net income?

A. $90,000.

B. $85,200.

C. $54,000.

D. $94,800.

E. $86,640.

The answer is B, but I am not sure how to get it.