(3) to print, circulate, or post or cause to be printed, circulated, or posted any advertisement or sign, or use any form of application for the purchase, rental, or lease of any real property or make any record or inquiry in connection with the prospective purchase, rental or lease of any real property, which expresses directly or indirectly, any limitation, specification or discrimination as to race, color, creed, religion, national origin, sex, gender identity, marital status, status with regard to public assistance, disability, sexual orientation, or familial status or any intent to make any such limitation, specification, or discrimination except that nothing in this clause shall be construed to prohibit the advertisement of a dwelling unit as available to adults-only if the person placing the advertisement reasonably believes that the provisions of this section prohibiting discrimination because of familial status do not apply to the dwelling unit.