Final answer:
Eligibility for Individual Disability Income benefits through Social Security arises when a disability is expected to last at least twelve months or is permanent, and the individual has a qualifying work history.
Step-by-step explanation:
After a disability, an insured individual is eligible for Individual Disability Income benefits upon demonstrating that the disability is expected to last at least twelve months or is permanent. The Social Security program, specifically the Old-Age, Survivors, and Disability Insurance (OASDI), requires workers to have a sufficient work history and meet the medical criteria for disability. For those whose disabilities do not allow them to remain in the workforce, Supplemental Security Income (SSI) provides additional assistance if they fall below certain income thresholds.