An insurer may invest in the bonds, debentures, or other securities of public housing authorities, issued under the act of Congress entitled the Housing Act of 1949 and approved July, 1949, the Municipal
Housing Commission Act, or the Rural Housing Commission Act, and any additional amendments issued by any other public housing authority or agency in the United States, if the bonds, debentures, or other securities are secured by a pledge of annual contributions to be paid by
the United States or any agency of the United States.