John is a stockbroker. He has had several job offers, but he has turned them down because he thinks he can find a firm that better matches his tastes and skills. Curtis has looked for work as an accountant for some time. While the demand for accountants doesn't appear to be falling, there seems to be more people applying than jobs available:
a. John and Curtis are both frictionally unemployed.
b. John and Curtis are both structurally unemployed.
c. John is frictionally unemployed, and Curtis is structurally unemployed.
d. John is structurally unemployed, and Curtis is frictionally unemployed.