Any person who is unable to sign his or her name shall, whenever his or her signature is required upon any document in terms of this Act, impress in place thereof his or her left thumb print upon the space within which he or she would otherwise have been required to sign his or her name, and if his or her left thumb print is not available, he or she shall in place thereof press another of his or her fingerprints, and in such latter event the document so marked shall be endorsed by the officer in whose presence the print was made, identifying the finger used.