Final answer:
Asthma is a chronic respiratory condition marked by inflammation and narrowing of the airways, causing difficulty in breathing. It can be triggered by allergens, exercise, stress, or cold air.
Step-by-step explanation:
Asthma is a chronic inflammatory disease of the airways in the lungs, in which the airways periodically become inflamed, causing swelling and narrowing of the airways. This leads to difficulty in breathing, wheezing, chest tightness, and coughing. Asthma can be triggered by various factors such as allergens, exercise, stress, or cold air.