Private fee-for-service (PFFS) plans are offered by private insurance companies in some regions of the country, and Medicare pays a pre-established amount of money each month to the insurance company, which decides how much it will pay for services. Such plans reimburse providers on a fee-for-service basis and are authorized to charge enrollees up to __________ percent of the plan's payment

schedule.
a. 50
b. 80
c. 100
d. 115

d