Which of the following would be an inappropriate treatment for a diver showing symptoms of Decompression Sickness?

Taking the victim back underwater is inappropriate for someone showing symptoms of Decompression Sickness (DCS). DCS occurs when nitrogen bubbles form in the body due to a rapid decrease in pressure, typically after ascending too quickly from a dive. Returning the diver to underwater conditions would exacerbate the problem, as the increased pressure could further complicate their condition and potentially lead to more severe symptoms or even life-threatening situations.

In contrast, administering pure oxygen is a standard treatment for DCS as it helps reduce the size of nitrogen bubbles and speeds up their absorption back into the bloodstream. CPR may be necessary if the diver is unresponsive or not breathing, which is crucial for their survival. Additionally, treating for shock is essential in providing overall care, ensuring that the victim is stabilized and monitored closely until more definitive treatment can be administered.