A policy of insurance or surety bond does not satisfy the financial responsibility requirements of this subpart unless the insurer or surety furnishing the policy or bond is—

(a) Legally authorized to issue such policies or bonds in each State in which the motor carrier operates, or

(b) Legally authorized to issue such policies or bonds in the State in which the motor carrier has its principal place of business or domicile, and is willing to designate a person upon whom process, issued by or under the authority of any court having jurisdiction of the subject matter, may be served in any proceeding at law or equity brought in any State in which the motor carrier operates; or

(c) Legally authorized to issue such policies or bonds in any State of the United States and eligible as an excess or surplus lines insurer in any State in which business is written, and is willing to designate a person upon whom process, issued by or under the authority of any court having jurisdiction of the subject matter, may be served in any proceeding at law or equity brought in any State in which the motor carrier operates.