Which of the following is a sign of neurotoxic snakebite?

C is identified as a sign of neurotoxic snakebite because neurotoxins primarily affect the nervous system, leading to symptoms such as paralysis. In the case of snakebites from venomous species that possess neurotoxic properties, one of the hallmark signs is descending paralysis. This means that the paralysis begins in the cranial areas (such as the face and mouth) and progresses downward, affecting the rest of the body. This progression can lead to serious implications, such as respiratory failure, as muscles necessary for breathing become paralyzed.

Conversely, the other options typically associated with snakebites involve different mechanisms or types of venom effects. Local bleeding tends to result from cytotoxic or hemotoxic venoms that damage blood vessels or platelets, while progressive edema is usually indicative of tissue damage or inflammation, not specifically neurotoxic activity. Tissue destruction is more commonly related to cytotoxic venom, which causes necrosis in the area surrounding the bite. Each of these symptoms reflects different types of envenomation and their respective pathophysiological effects, highlighting why descending paralysis is the defining sign of neurotoxic snakebites.