Any person who is entitled to appear before any authority other than the High Court in connection with any proceedings under this Act may be represented before such authority-

(a) by his relative or a person regularly employed by him, if such relative or person is duly authorised by him in writing in this behalf; or

(b) by a legal practitioner; or

(c) subject to such conditions, as may be prescribed, by an accountant or a value added tax practitioner possessing the prescribed qualifications and duly authorised by him in writing in this behalf.