When Adding Objects to a Sterile Field, What Action Does

When adding objects to a sterile field, what action does the nurse take?

A) Peel the wrapper open, invert the package, and drop the item on the sterile field.
B) Open items as close to the sterile field as possible to avoid contamination.
C) Peel open the outer package and lay the item on the sterile field to open later.
D) Once a sterile field is set, no more items can be introduced to it.