A Patient in Traction with a Fractured Hip Is Diagnosed

A patient in traction with a fractured hip is diagnosed with a stage I pressure ulcer.She asks the nurse how a pressure ulcer could occur after only 2 days of immobility.The nurse's response is based on her knowledge that:

A) "Erythema can occur in 1 to 2 hours, even in a person with healthy skin and adequate circulation."
B) "It takes several days for a pressure ulcer to form."
C) "The pressure ulcer probably occurred when you fell."
D) "The cause of pressure ulcers isn't really known."