Emphysema is a lung condition that causes shortness of breath. In people with emphysema, the air sacs in the alveolar are damaged. Over time, the inner walls of the air sacs weaken and rupture - creating larger air spaces instead of many small ones. This affects their ability to breathe normally. This reduces the surface area of the lungs and, in turn, the amount of oxygen and carbon dioxide that reaches your bloodstream.
The answer is A. Emphysema is a chronic respiratory disease in which there is over-inflammation in the alveoli in the lungs. Causing a decrease in lung function, and leaving people breathless.