Which feature helps to limit an insured's out-of-pocket expenses in major medical policies?

The stop-loss feature in major medical policies is designed to protect the insured by setting a limit on their out-of-pocket expenses for covered medical services within a policy year. Once the insured's expenses reach this predetermined threshold, the insurance company takes over and pays 100% of the eligible costs for the remainder of the year. This feature is crucial as it effectively caps the financial risk that an individual faces, ensuring that no matter how extensive their medical needs are, they will not exceed a certain financial burden.

The other options, such as the annual maximum limit, might define the maximum amount the insurer will pay for claims in a given year, but they do not directly limit the insured's out-of-pocket costs. An expedited claims process refers to the speed at which claims are handled and does not address the financial limits of the insured's responsibilities. Coverage for pre-existing conditions ensures that individuals can receive treatment for their existing health issues, but it does not directly correlate to limiting out-of-pocket expenses. The stop-loss feature directly addresses financial protection, making it the correct choice in this context.