Final answer:
The exact average monthly premium for Medicare Part D during 2016 is not given, but funding for Part D comes from beneficiary premiums and general revenues, with the projected cost of the benefit estimated at $121 billion for that year.
Step-by-step explanation:
The question asks about the average monthly premium for Medicare Part D in 2016. Medicare Part D is a prescription drug benefit program that is part of the broader Medicare system, which is a health insurance program mainly for individuals aged 65 and older, as well as some younger people with disabilities. While the exact average monthly premium for Medicare Part D in 2016 is not provided in the supplied reference texts, we do know that Medicare Part D premiums are financed through beneficiary premiums (about 25%) and general revenues (about 75%).
In 2016, the Medicare system projected that the prescription drug benefit's annual cost would rise to $121 billion. Considering that individuals enrolled in this part pay an annual premium and deductible for federal government to cover 75% of their prescription drug costs up to $2,250, we can infer that the costs were substantial, reflecting wider healthcare spending trends.