Which of the following conditions is characterized by a sudden onset of difficulty in breathing due to air trapping?

The correct answer is asthma because it is a condition that is primarily characterized by acute episodes of airway obstruction due to bronchial hyperreactivity. During an asthma attack, the airways become narrowed and inflamed, leading to difficulty in breathing and the sensation of air trapping. This sudden onset of respiratory distress can be triggered by various factors, such as allergens, respiratory infections, or physical activity, making it a hallmark of the condition.

Asthma attacks often result in wheezing, coughing, and difficulty exhaling, which are symptoms associated with the obstruction of airflow. The intermittent nature of these episodes, along with the immediate response to bronchodilator medications, reinforces the characterization of asthma as a condition involving sudden breathing difficulties due to air trapping.

Other conditions listed, while related to respiratory issues, have different underlying mechanisms and symptoms. Pneumonia involves inflammation of the lung tissue, typically leading to fluid accumulation rather than the acute airway obstruction seen in asthma. Chronic bronchitis is a condition associated with long-term cough and sputum production, often as a part of Chronic Obstructive Pulmonary Disease (COPD) where airflow limitation is more chronic than acute. Emphysema, another form of COPD, involves the destruction of alveoli, leading to