What measures should be taken for a person affected by a choking agent?

The correct response highlights the importance of specific care for individuals affected by a choking agent, such as a chemical or toxic gas that can impair breathing. Loosening clothing helps relieve any constriction around the chest and abdomen, which can be critical for someone struggling to breathe. Avoiding exertion is vital because physical activity can increase the body's demand for oxygen and exacerbate breathing difficulties. Keeping the affected person warm can also help reduce stress on their body during recovery and maintain their vital signs, as exposure to choking agents can cause shock.

In contrast, encouraging physical activity would likely worsen the situation by putting additional strain on the respiratory system. Providing water immediately might not be appropriate, as the person may have difficulty swallowing or could be at risk of choking again. Administering first aid for wounds would not directly address the immediate risks posed by a choking agent, which primarily affects breathing rather than causing external injuries.