A patient of Dr. Jones presents his Medicare card after his appointment. The total charge for the services was $100; however, Medicare will pay only $60 for this service and the patient is to pay $20. Acceptance of the patient's Medicare insurance creates a contract:

for $20 and an $80 discount or price concession.

for payment of $60 and a price concession of $40.

for payment of $80 and a $20 discount or price concession.

for payment of $100, regardless of what Medicare will pay.