Final answer:
A supplemental extended reporting period extends coverage for 12 months.
Step-by-step explanation:
The answer to this question is C. for 12 months. A supplemental extended reporting period provides an additional period of time for reporting claims to an insurance company after a policy has expired. It allows policyholders to report claims even after the policy has ended, as long as the claim arises from an incident that occurred during the policy period. This coverage extension usually lasts for 12 months but can vary depending on the specific policy.