DNA protection assays identify specific nucleotide-protein contacts. What is the role of deoxyribonuclease (DNase) I treatment in footprint analysis?

A) DNase I is used to break DNA previously bound to protein.
B) Protein-bound DNA is protected from DNase I and it can be isolated and characterized.
C) DNase I prepares protein-bound DNA for sequencing.
D) DNase I is used to cleave Taq polymerase.
E) DNase I synthesizes DNA from the upstream primer.