Jose rents office space for $20,000 per year. He uses the office to fill out tax returns for 1<000 clients per year. If the office rent increases to $25,000 per year, the marginal cost of filling out tax returns will:
A. Not change
B. Increase by $5000
C. Increase, but we cannot determine the amount of the increase with the information given.
D. Increase by $5