What provision in a health insurance plan helps to avoid overinsurance for a person covered by more than one plan?

The provision that helps to avoid overinsurance for a person covered by more than one health insurance plan is known as coordination of benefits. This mechanism ensures that when an individual is covered by multiple health plans, the total benefits paid do not exceed the actual medical expenses incurred. It outlines the order in which multiple insurers will pay claims, ensuring that one policy pays first (the primary insurer) and the second policy pays the remainder (the secondary insurer), up to the limits of that plan.

By coordinating benefits, insurers prevent duplication of payments and ensure that the total reimbursement aligns with the medical expenses. This is crucial to maintaining the integrity of the insurance system, allowing multiple coverages without providing an unfair financial advantage to the insured.

The other options pertain to different aspects of insurance management. Subrogation involves the insurance company's right to pursue a third party for damages after paying a claim. Eligibility verification ensures that the insured meets the necessary criteria for coverage. Cost-sharing involves the arrangement between the insurer and the insured regarding payments like deductibles and co-pays as part of utilizing an insurance policy, but it does not specifically address coordination across multiple policies.