What happens when a drowning person tries to breathe?

When a drowning person attempts to breathe, they instinctively try to inhale, and this reflex can lead them to swallow substantial amounts of water instead of air. This situation occurs because the airway is compromised, and as the individual gasps for air, water can enter the mouth and throat. This intake can severely compromise their ability to breathe and increases the risk of aspiration, which is when water enters the lungs and leads to further respiratory distress.

While the other options describe effects that could occur during a drowning incident, they do not accurately capture the direct response of trying to breathe. For instance, if large amounts of water go into the lungs, it generally happens after aspiration rather than the act of attempting to breathe. The heart stopping can be a later consequence of drowning due to lack of oxygen, and while bubbles may exit the nose during drowning, this is more of a result than a primary reaction to the act of trying to breathe. Thus, the response of swallowing water directly relates to the instinctive attempts of the body to acquire air during an emergency.