Final answer:
The correct statements regarding cryotherapy are both A and B, as its primary goal is to reduce inflammation post-injury and cold applications should be removed if skin discoloration like redness or blueness occurs to prevent exacerbating ischemia.
Step-by-step explanation:
The correct answer to the student's question is C. Both A and B. The application of ice, or cryotherapy, is primarily used to reduce inflammation, which makes it the treatment of choice in the first 24-48 hours following a musculoskeletal injury. This aligns with the first step in a typical physical therapy plan directed at managing inflammation and swelling post-injury. Secondly, it is essential to remove cold applications from areas that have turned red or blue during therapy. Persisting with cryotherapy in these circumstances can exacerbate ischemia, therefore, monitoring skin color changes during therapy is crucial.