(1)  The authorities shall exercise all or any of the powers and perform all or any of the functions conferred on, or, assigned, as the case may be, to such authorities by or under this Act or the rules framed thereunder in accordance with such directions as the Central Government may issue for the exercise of powers and performance of the functions by all or any of the authorities.

   (2)  In issuing the directions or orders referred to in sub-section (1), the Central Government may have regard to any one or more of the following criteria, namely:—

   (a)  territorial area;

   (b)  classes of persons;

   (c)  classes of cases; and

   (d)  any other criterion specified by the Central Government in this behalf.