What document authorizes an insurer to conduct business as an admitted insurer?

The correct answer is the certificate of authority, which is the key document that permits an insurer to operate as an admitted insurer within a specific jurisdiction. This certificate is issued by the state’s insurance department after the insurer has fulfilled all regulatory requirements, demonstrating that it meets the necessary financial, legal, and operational standards to offer insurance products to consumers. Having this certificate allows the insurer to partake in the state's insurance business, providing policyholders with access to the protections and solvency requirements outlined by state laws.

The other options, while related to the operations of insurance companies, do not specifically grant the authority to conduct business. For example, a license to transact generally refers to authorization at a more granular level, potentially for individual agents rather than the company as a whole. An insurance charter establishes the corporation's existence but does not allow it to engage in business until the certificate of authority is obtained. Regulatory compliance forms are important for ensuring ongoing adherence to state laws but do not serve as a basis for initially starting operations.