Which physical sign indicates a possible issue with sudden environmental changes?

The physical sign that most clearly indicates a possible issue with sudden environmental changes is mottled skin. Mottled skin can be a sign of inadequate blood flow or oxygenation, often resulting from environmental factors such as rapid altitude changes, extreme temperatures, or exposure to toxins. When the body is subjected to sudden environmental changes, it may struggle to maintain homeostasis, leading to visible symptoms like mottling.

While other options may represent physical responses to different conditions, they don't specifically relate to sudden environmental changes in the same way that mottled skin does. For example, explosive noise doesn’t indicate a physical response of the body; rather, it's an auditory event. A dry cough might suggest respiratory issues, which could be relevant but is not directly tied to sudden environmental changes. Partial paralysis could indicate severe neurological issues, potentially resulting from a sudden trauma rather than a gradual change in the environment. Therefore, mottled skin is the best indicator of a body reacting to significant, rapid environmental changes.