Which of the following is a primary cause of COPD?

Smoking is a primary cause of Chronic Obstructive Pulmonary Disease (COPD). It is the most significant risk factor for developing COPD, as it leads to inflammation and damage in the airways and lung tissue. Cigarette smoke contains numerous toxins and irritants that can cause chronic bronchitis and emphysema, the two main conditions that constitute COPD. Long-term exposure to smoke can lead to airflow limitation, breathlessness, and an increase in respiratory infections due to compromised lung function.

While chronic respiratory infections, environmental allergies, and genetic predispositions can contribute to respiratory issues, they are not considered primary causes of COPD. Smoking remains the leading cause globally, making it a critical factor in both the development and progression of the disease.