A 1-Inch Margin Around a Sterile Field Is Contaminated

A 1-inch margin around a sterile field is contaminated. Which statement is correct?

A) All sterile items must be placed inside the 1-inch margin.
B) Items outside the 1-inch margin are clean but not sterile.
C) You can change the margin to 1/2 inch if you need a bigger sterile field.
D) You must tell the resident if you contaminate the sterile field.