What type of coverage does an endorsement typically modify?

An endorsement is a modification added to an insurance policy that changes its original terms, coverages, or limits. This can include adding or excluding coverage for specific events, altering the limits of coverage for certain types of risks, or defining new terms for how the policy operates.

By focusing specifically on the terms, coverages, and limits of a policy, endorsements allow insurers and policyholders to tailor their coverage to meet particular needs or to adjust based on changing circumstances. This flexibility is one of the key features of insurance policies, as it enables individuals and businesses to adapt their coverage without needing to rewrite the entire contract.

While other options mention aspects like the premium amount, duration, or an entire portfolio, these do not accurately reflect the primary function of endorsements, which is centered on modifying specific aspects of individual policy coverage. Therefore, the correct answer emphasizes the crucial role endorsements play in redefining policy specifics, ensuring that insurance coverage remains relevant and adequate to the policyholder's needs.