A coal miner earns more than someone with a similar background and skills who works in a safer job. What does this show?

1. A Option A: Coal miners must have greater human capital than others
2. B Option B: We have evidence of discrimination against workers outside the coal mine
3. C Option C: Coal miners must be more attractive than other workers
4. D Option D: We have observed a compensating differential

Answer checked 11 October 2026 · How we write and check questions