Medical Expense✓ Verified · outline & fact-checked · Sep 2026Difficulty 2/5
A person who is not 'fully insured' under Social Security but has earned 30 to 39 work credits must:
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Answer & full 3-part explanation (select an option above, or peek)
Why B is correct
Individuals who are not fully insured under Social Security must pay a monthly premium for Medicare Part A coverage. There are two premium tiers: those with 30 through 39 work credits pay a reduced monthly premium, while those with 0 through 29 credits pay a higher monthly premium. The premium amount is set by law and adjusts annually. Fully insured individuals, generally those with 40 credits, receive Part A without a monthly premium.
Why the other options are wrong
- A) A person with only 30 to 39 credits is not fully insured and must pay a monthly Part A premium rather than receiving it free.
- C) There is no age-70 waiting period for Part A enrollment; the issue is the premium tied to work credits.
- D) Buying Part A does not require enrolling in Part B first; Part B is optional and separate from the Part A purchase.
Memory hook
Fully insured means 40 credits and free Part A. 30-39 credits means a reduced premium; 0-29 means the higher one.