The Head Librarian Issued a Directive That "Absolutely No Food

The head librarian issued a directive that "Absolutely no food or drink are allowed in the library." She issued this directive because several computers and keyboards in the computer labs, as well as several study cubes, were recently damaged by spilled drinks and food. This is a(n) ________ issued by the librarian.

A) procedure
B) industry standard
C) rule
D) level of certification
E) certified procedure