Final answer:
Before the ACA, health insurance underwriters could deny coverage based on pre-existing medical conditions. The ACA mandates everyone to buy health insurance and prevents denial based on those conditions, but employment status can still affect access to health insurance.
Step-by-step explanation:
A health insurance underwriter may deny coverage for a number of reasons. Prior to the Patient Protection and Affordable Care Act (ACA), insurance companies frequently used pre-existing medical conditions as a reason to deny coverage or charge higher prices. The ACA sought to address the issue of adverse selection and the high number of uninsured Americans by mandating that everyone buy health insurance and preventing providers from denying individuals based on pre-existing conditions. While the ACA made strides in addressing this, other factors such as employment status still influence an individual's ability to obtain group health insurance through their employer.