Bonds issued under former Act No. 326 of the Public Acts of 1988 or part 193 are made securities in which banks, savings and loan associations, investment companies, credit unions, and other persons carrying on a banking business; all insurance companies, insurance associations, and other persons carrying on an insurance business; and all administrators, executors, guardians, trustees, and other fiduciaries may properly and legally invest funds, including capital, belonging to them or within their control.