Which of the following is NOT considered a life-threatening injury in an aquatic environment?

In an aquatic environment, a life-threatening injury typically poses an immediate risk to an individual's life or requires urgent medical intervention. Minor scrapes, while they may cause discomfort or require basic first aid, do not usually endanger a person's life or health in the same way that the other options do.

Submersion can lead to drowning, which is a significant life threat. Cardiac emergencies, such as heart attacks, require immediate action to prevent fatal outcomes. Severe bleeding can lead to shock and death if not treated promptly. In contrast, minor scrapes generally do not require urgent medical care and are not life-threatening in nature. Therefore, they stand out as the option that does not fit the category of life-threatening injuries in an aquatic setting.