Under Social Security, which of the following determines the amount of a worker's Disability Income...

A. Primary Insurance Amount (PIA) is correct. Social Security Disability Insurance benefits are calculated from the worker's Social Security earnings record. The central benefit figure produced from that earnings record is the worker's Primary Insurance Amount .

The Social Security Administration states directly that a disabled worker's monthly disability benefit is generally equal to the worker's PIA. The PIA itself is computed using the worker's indexed earnings under the Social Security benefit formula. SSA also describes the PIA as the basic figure used to determine cash benefits payable to workers and, where applicable, their dependents and survivors.

Option B is incorrect because national wage levels may influence indexing factors used within Social Security calculations but do not themselves constitute the individual worker's disability benefit. Option C is incorrect because Social Security Disability Insurance is a federal program; a person's state of residence does not set an average wage used as that individual's benefit amount. Option D confuses the Social Security taxable wage base with benefit computation.

The examination logic therefore requires distinguishing the worker-specific benefit measure—PIA—from broader wage statistics and payroll-tax concepts.

Reference topics: Social Insurance and Retirement Concepts; Social Security Disability Benefits; Primary Insurance Amount.

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