As Akerlof argues, sellers who have a lemon, of course, know they have lemon but are not willing to tell the truth about the condition of their auto and, for the short selling period involved, can put their auto in a satisfactory condition that

approximates the normal condition of the auto that are not lemons. In subsequent literature, this problem called the _ problem.
a. informational asymmetry
b. agency
c. moral hazard
d. certification

C