Which of the following pressure ulcer stages may present as a shallow open ulcer with a red/pink wound bed and no sloughing?

The correct answer, Stage II, accurately describes the characteristics of a pressure ulcer at this stage. Stage II pressure ulcers are classified as partial-thickness skin loss, which may present as a shallow open ulcer. This shallow ulcer typically has a red or pink wound bed without any slough and may involve the epidermis and dermis. The absence of slough is a key indicator distinguishing it from more advanced stages.

In Stage I, the skin is intact but shows localized redness, which does not indicate an open ulcer. Stage III involves full-thickness tissue loss where subcutaneous fat may be visible, often with slough present, thus exceeding the description provided. Stage IV represents a more severe ulcer with full-thickness tissue loss, exposing muscle, bone, or tendons, which also does not align with the characteristics of a Stage II ulcer. Therefore, the features outlined in the question are consistent only with Stage II pressure ulcers.