Cough and congestion can result from breathing which of the following?

Breathing in sulfur dioxide can lead to cough and congestion due to its irritant effects on the respiratory tract. Sulfur dioxide is a colorless gas with a sharp smell, commonly produced from the burning of fossil fuels. When inhaled, it can cause immediate irritation to the throat and lungs, leading to symptoms such as coughing and congestion as the body attempts to expel the irritant.

The effects of sulfur dioxide are particularly pronounced in individuals with pre-existing respiratory conditions, such as asthma or chronic bronchitis, making it a significant air pollutant of concern. Inhalation of even low concentrations can lead to increased mucus production and respiratory discomfort, aligning with the symptoms described in the question.

Other substances listed, while potentially harmful, do not primarily lead to cough and congestion in the same way. For instance, carbon monoxide is a colorless, odorless gas that primarily interferes with the body's ability to transport oxygen, leading to different symptoms, while tear gas is intended for crowd control and causes eye and respiratory irritation but is not typically encountered in the same environmental contexts as sulfur dioxide. Carbon dioxide, while it can cause respiratory problems in high concentrations, does not usually cause cough and congestion at normal environmental levels. Thus, sulfur dioxide is the