Which of these gases can lead to asphyxiation by displacing oxygen?

Many gases can lead to asphyxiation by displacing oxygen in an environment. When these gases accumulate, they can reduce the concentration of oxygen available for breathing, which is essential for human survival.

Carbon dioxide is produced naturally during respiration and can accumulate in confined spaces, leading to asphyxiation when it displaces oxygen. Helium, while often associated with lighter-than-air balloons, displaces oxygen as well. When inhaled in high concentrations, it can prevent oxygen from reaching the lungs. Nitrogen, a naturally occurring gas that makes up a significant portion of the Earth's atmosphere, can also pose a risk in enclosed spaces. If the nitrogen concentration increases significantly while reducing oxygen levels, it can lead to asphyxiation.

Since all these gases can displace oxygen and potentially lead to asphyxiation in sufficient concentrations or confined spaces, the correct choice encompasses all options provided. This understanding is crucial for safety practices, especially in settings where various types of gases may be used or stored.