Richard sold a rare automobile he had held as an investment in 2018. Richard purchased the automobile in 1993; its adjusted basis at the time of the sale was $70,000, and the selling price was $250,000. Richard received $50,000 in 2018 and was to receive

$50,000 per year plus interest in each of the four succeeding years. On January 5, 2020, Richard sold the installment obligation (he did not receive an installment payment in 2020) for $145,000. Richard’s gain on the sale of the installment obligation in 2020 is:

a. $42,000

b. $72,000

c. $103,000

d. $108,000

e. $150,000