For the purposes of this Act, there shall be the following classes of income-tax authorities: —

(a) the Central Board of Direct Taxes constituted under the Central Boards of Revenue Act, 1963;

(b) Principal Directors General of Income-tax or Principal Chief Commissioners of Income-tax;

(c) Directors General of Income-tax or Chief Commissioners of Income-tax;

(d) Principal Directors of Income-tax or Principal Commissioners of Income-tax;

(e) Directors of Income-tax or Commissioners of Income-tax or Commissioners of Income-tax (Appeals);

(f) Additional Directors of Income-tax or Additional Commissioners of Income-tax or Additional Commissioners of Income-tax (Appeals);

(g) Joint Directors of Income-tax or Joint Commissioners of Income-tax or Joint Commissioners of Income-tax (Appeals);

(h) Deputy Directors of Income-tax or Deputy Commissioners of Income-tax;

(i) Assistant Directors of Income-tax or Assistant Commissioners of Income-tax;

(j) Income-tax Officers;

(k) Tax Recovery Officers; and

(l) Inspectors of Income-tax.