Final answer:
The term for ongoing diseases characterized by diminished airflow during expiration is d) COPD. COPD encompasses conditions like emphysema, where alveoli are destroyed, reducing gas exchange and causing trapped air in the lungs during exhalation.
Step-by-step explanation:
The term that refers to ongoing diseases characterized by diminished airflow during expiration is d) COPD (Chronic Obstructive Pulmonary Disease). COPD is a lung condition that reflects chronic poor airflow and includes diseases such as emphysema and chronic bronchitis. The symptoms, such as shortness of breath and a cough that produces phlegm, typically worsen over time. In emphysema, a component of COPD, the walls of the alveoli are destroyed, decreasing the lung's surface area for gas exchange and reducing the elasticity of alveoli. This causes a breakdown of connective tissues, leading to difficulty expelling air from the lungs during exhalation, thus trapping air in the lungs and hampering gas exchange. Unlike COPD, asthma is characterized by airway inflammation and bronchospasms, which can inhibit air from entering the lungs, but it does not inherently involve the long-term degraded elasticity and alveolar breakdown that COPD does.