Which Statement Appearing Below Correctly Describes the IRS Letter Ruling

Which statement appearing below correctly describes the IRS letter ruling process?

A) In certain situations, the IRS will not issue a ruling.
B) Some letter rulings are of such importance and general interest that they are later published (in anonymous form) as Revenue Rulings.
C) Letter rulings benefit both taxpayers and the IRS.
D) Letter rulings are open to public inspection after removing identifying information.
E) All of the above are correct.