Which of the following is a recommended safety measure against hypothermia?

Wearing appropriate clothing is essential to prevent hypothermia as it helps maintain body temperature in cold environments. Appropriate clothing typically includes layers that trap heat while allowing moisture to evaporate, thus keeping the body warm and dry. This practice of layering is important because it creates insulation and provides a buffer against cold air, reducing the risk of heat loss from the body. Additionally, clothing made from moisture-wicking fabrics can help to manage sweat, which is crucial since getting wet from either sweat or external sources significantly increases the risk of hypothermia.

The other options present unsafe practices that can increase the risk of hypothermia. Tight clothing can restrict blood flow and limit insulation. Exercising on slippery surfaces is dangerous and does not relate directly to hypothermia prevention, and avoiding layers is counterproductive, as layers are essential for effective thermal management. Thus, wearing appropriate clothing is the best recommendation for safety against hypothermia.