XYZ company has the following transactions over the year. What is the net income for the year? (SHOW CALCULATION PLEASE)

Credit sales	$100,000
Tax expenses	$4,000
Cost of goods sold	$90,000
Cash received from customers for work to be performed next year	$10,000
Operating expenses	$55,000
Cash sales	$75,000
Interest expenses	$5,000
Gain on sale of equipment	$2,500

A. $40,000

B. $31,000

C. $23,500

D. $21,000