Under O.C.G.A. § 33-3-2, an insurer that transacts insurance in Georgia without first obtaining a certificate of authority from the Commissioner is best described as:

Why this is the answer

O.C.G.A. § 33-3-2 prohibits transacting insurance in Georgia without complying with the certificate-of-authority provisions of Title 33. An insurer that has not obtained authority is termed an 'unauthorized insurer.' Admitted (authorized) insurers hold a current certificate. Surplus lines insurers are technically non-admitted but may still write eligible coverage through a licensed surplus lines broker under Article 2 of Chapter 5 (§§ 33-5-20 et seq.). A domestic reciprocal is an organizational form, not an authority status.