Which of the following claims is true about a "fully insured" worker?

A "fully insured" worker status is attributed to individuals who have accumulated a specific number of work credits through their employment history. In the United States, a worker qualifies as fully insured if they have earned at least 40 credits, which typically equates to about 10 years of work. Each year of work allows a worker to earn up to four credits, so achieving 40 credits demonstrates a significant period of workforce participation, which is essential for eligibility in benefit programs such as Social Security Disability Insurance (SSDI).

The other claims, while they may seem related to the insurability of a worker, do not accurately define the status of being fully insured. For instance, while working for 20 years may contribute to earning the requisite credits, it is not a strict requirement since the focus is on the number of credits rather than the duration of employment. Reaching age 65 is associated with retirement benefits rather than the definition of being fully insured. Additionally, the necessity of having received benefits within the last 10 years pertains more to the criteria for qualifying for certain benefits rather than defining a fully insured status. Thus, the most accurate statement regarding a fully insured worker is that they must have earned at least 40 credits.