A Patient Asks the Nurse, "What Do Health Maintenance Organizations

A patient asks the nurse, "What do health maintenance organizations (HMOs) do to reduce health care costs?" The response giving the best example of an HMO cost-containment method would be:

A) "HMOs pool individual contributions for use in catastrophic illness."
B) "HMOs provide supplemental coverage for items not covered by Medicare."
C) "HMOs use a retrospective payment system."
D) "HMOs provide services aimed at keeping members healthy."