The correct answer is option 2, sneezing. When we breathe in polluted air, we may inhale small particles called particulate matter (PM-10). These particles can irritate the respiratory system and cause health problems. However, our body has protective mechanisms to filter out these particles. One of these mechanisms is sneezing. When there are irritants, like PM-10, in the airways, the body triggers a sneeze reflex. This reflex involves forcefully expelling air from the nose and mouth, along with any particles that may be present. Sneezing helps to clear the airways and remove the particulate matter, reducing the potential harm it can cause. Coughing (option 1) is also a protective mechanism to expel irritants and clear the airways, but it is not specifically targeted at filtering out particulate matter. Urination (option 4) is unrelated to the exhalation of particulate matter.