If a diver shows signs of heat exhaustion, what is the recommended action?

When a diver shows signs of heat exhaustion, the primary goal is to cool them down and rehydrate them. Removing the exposure suit helps facilitate this process by allowing the body to cool more effectively. Exposure suits can retain heat, which is counterproductive when dealing with heat exhaustion. Hydration is equally important, as heat exhaustion can lead to dehydration, which exacerbates the condition. Providing fluids helps restore lost electrolytes and maintain proper body function.

The other choices would not effectively address the immediate needs of someone suffering from heat exhaustion. Encouraging a diver to dive again could worsen their condition. Giving caffeine might not be advisable, as it can contribute to dehydration. Wrapping someone in warm towels is also inappropriate, as it would increase their body temperature rather than help cool them down. Thus, removing the exposure suit and ensuring proper hydration is the key response in managing heat exhaustion in divers.