When working with Dr. Brennan under the PFFS plan terms, how much may Dr. Brennan charge Mary Rodgers?

The correct choice indicates that Dr. Brennan may charge no more than the co-payment set in the PFFS plan's terms. This is because PFFS plans, which are a type of Medicare Advantage plan, have specific contractual agreements that detail the cost-sharing requirements for services rendered, including co-payments.

Under these plans, providers are permitted to establish certain co-payment amounts, and Mary's financial responsibility is outlined within those plan terms. Dr. Brennan is therefore bound to adhere to the limits set forth in the PFFS plan regarding the co-payment; she cannot impose any additional charges outside what is defined in the plan. This ensures that both the provider and the patient are aligned with Medicare regulations and the specific terms of the PFFS arrangement.

In contrast, the other options suggest scenarios that either allow for unlimited charging or do not align with the regulations governing Medicare Advantage plans. Therefore, the selection of the co-payment set in the plan as the upper limit for charges reflects the adherence to those established guidelines.