Could you please explain this question step by step? Thank you

A business operated at 100% of capacity during its first month and incurred the following costs:

Production costs (5,000 units):
Direct materials	$70,000
Direct labor	20,000
Variable factory overhead	10,000
Fixed factory overhead	2,000	$102,000
Operating expenses:
Variable operating expenses	$17,000
Fixed operating expenses	1,000	18,000

If 1,000 units remain unsold at the end of the month and sales total $150,000 for the month, the amount of operating income reported on the absorption costing income statement would be

a.$68,400

b.$52,000

c.$50,400

d.$70,000