A patient is admitted to the hospital with a pressure ulcer on the sacrum.The wound is open with exposed bone.The nurse should document this pressure ulcer at what stage?

A) Stage I
B) Stage II
C) Stage III
D) Stage IV

Stage IV: Full-thickness tissue loss with exposed bone,tendon,or muscle; slough or eschar may be present; often includes undermining and tunneling
Stage I: Intact skin with nonblanchable redness of a localized area,usually over a bony prominence
Stage II: Partial-thickness loss of dermis presenting as a shallow open ulcer with a red-pink wound bed,without slough; may also present as an intact or open/ruptured serum-filled blister
Stage III: Full-thickness tissue loss; subcutaneous fat may be visible,but bone,tendon,or muscle is not exposed; slough may be present but does not obscure the depth of tissue loss; may include undermining and tunneling