Emphysema is a kind of chronic obstructive pulmonary disease or COPD that which involves physiological abnormalities which includes loss of lung elasticity and air sac enlargement. It all starts when the alveoli or the air sac at the end of the bronchioles becomes enlarged due to its walls breaking down or are destroyed, collapsed, narrowed, stretched or over-inflated. Because of this, there will be fewer and larger damaged sacs which would eventually result to a reduced oxygen and carbon dioxide exchange in the surface area of the lungs. This would lead to a medical condition termed as respiratory acidosis because the lungs are incapable of removing enough carbon dioxide produced by the body.
Therefore, the answer is letter C. CHRONIC RESPIRATORY ACIDOSIS.
