Marine Corporation collected $120,000 during 2020. Of this amount, $2,000 was still unearned as of December 31, 2020. The company reported sales of $128,000. Marine purchased inventory during 2020 of $48,000, and the inventory account balance was the same at the beginning and the end of the year. What was the company's gross profit for 2020?

A.$42,000

B.$80,000

C.$78,000

D.$40,000

E. None of the above