Troy, a minor, sells his collection of sports memorabilia to Vern for $250. On his eighteenth birthday, Troy learns that the collection may have been worth at least $2,500. Troy

a. can disaffirm because the contract has not been fully performed.

b. can disaffirm if he does so within a reasonable time after attaining majority.

c. cannot disaffirm because he has already attained majority.

d. cannot disaffirm because the contract has been fully performed.