What are the primary physical symptoms caused by exposure to nitrogen dioxide (NO2)?

The correct choice identifies irritation of the nose and throat as primary physical symptoms caused by exposure to nitrogen dioxide (NO2). This is particularly relevant because nitrogen dioxide is a known respiratory irritant. When inhaled, NO2 can cause inflammation and irritation in the upper respiratory tract, leading to symptoms such as coughing, wheezing, and sensations of tightness in the throat.

In more severe cases, exposure to high levels of NO2 can lead to more serious respiratory issues, potentially resulting in suffocation due to the compromised function of the airways. Understanding these symptoms is crucial, especially for individuals working in environments where nitrogen dioxide may be present, as it emphasizes the importance of personal protective equipment and immediate medical attention if such exposure occurs.

The other choices do not accurately reflect the primary effects of nitrogen dioxide exposure, focusing instead on symptoms that are either less relevant or not directly associated with nitrogen dioxide. For instance, while headaches and dizziness can be caused by various factors, they are not the most immediate or characteristic responses to NO2.