Edison Company has 5,000 obsolete desk lamps that are carried in inventory at a manufacturing cost of $45000. If the lamps are reworked for $20,000, they could be sold for $37,000. Alternatively, the lamps could be sold for $9,000 for scrap. In a decision model analyzing these alternatives, the sunk cost would be:
a. $9,000
b. $8,000
c. $43,000
d. $45,000