Which of the following is NOT true of Medicare Supplement Insurance Plans?

Medicare Supplement Insurance Plans, often referred to as Medigap policies, are designed to fill in the gaps left by Original Medicare. While these plans offer various benefits to help cover out-of-pocket costs associated with Medicare Part A and Part B, they do not provide coverage for prescription drugs.

Therefore, saying that they cover all prescription drug costs is not true. In fact, beneficiaries who want prescription drug coverage typically need to enroll in a separate Medicare Part D plan, as Medigap policies specifically exclude this coverage. This emphasizes the importance of understanding that while Medigap can alleviate some costs associated with hospital stays and outpatient services, it does not extend to prescription medications.

The other options highlight accurate characteristics of Medicare Supplement Insurance Plans: they do adjust their benefit amounts in line with Medicare's changes, allow members the flexibility to choose any doctor that accepts Medicare, and they help cover costs that Original Medicare does not, such as copayments, coinsurances, and deductibles.