The bonds of the authority are securities in which all public officers and bodies of this state and all counties, cities, municipal corporations, and political subdivisions, all banks, bankers, trust companies, savings banks and institutions, building and loan associations, savings and loan associations, investment companies, insurance companies and associations, and all executors, administrators, guardians, trustees, and other fiduciaries may legally invest any sinking funds, moneys, or other funds belonging to them or within their control.