Which of the following is a key responsibility of the insurer related to claims?

The insurer's primary responsibility in relation to claims is to exercise the burden of proof. This means that when a claim is filed, the insurer is tasked with gathering evidence and information necessary to support their evaluation and decision regarding that claim. This includes determining whether the claim is valid based on the policy coverage and the facts of the loss.

In handling claims, insurers must provide sufficient evidence if they deny a claim or dispute the amount being claimed by the policyholder. This responsibility ensures that claims are managed fairly and in accordance with the terms outlined in the insurance policy. The burden of proof is a fundamental component of the claims process, as it establishes the framework within which both insurers and policyholders operate during dispute resolution.

The other options reflect activities that are either not standard responsibilities of insurers during the claims process or don't directly relate to the assessment of claims. Modifying policy benefits falls outside a claim's direct handling; performing a mortgage evaluation is generally not a core duty of an insurer in claims management; and determining supermarket liabilities doesn't pertain to the core responsibilities related to insurance claims.