(A-E) Asthma: This is an allergic disease. The muscles of the wall of the trachea remain excited and possess continuous contraction. Allergy-inducers in the air are responsible for this. Asthma causes difficulty in breathing and wheezing due to inflammation of bronchi and bronchioles.
$(B)$ Emphysema: This is a chronic lung disease. In this disease,alveoli lose their elasticity. As a result,gaseous chambers remain filled with air after expiration. It is mainly caused due to cigarette smoking and chronic bronchitis.
$(C)$ Bronchitis: It is the inflammation of the bronchi. It is caused due to smoking and infection. Continuous coughing is observed.
$(D)$ Pneumonia: It is a disease caused due to bacterial infection. Alveoli get filled with fluid and dead white blood cells. It is more dangerous in children,old people,and patients with $AIDS$.
$(E)$ Occupational Respiratory Disorders: These are caused due to one's occupation. Gases and dust particles are major causative agents. Common examples are silicosis and asbestosis. In certain industries,especially those involving grinding or stone-breaking,so much dust is produced that the body's defense mechanism cannot fully cope. Long exposure can lead to inflammation,causing fibrosis (proliferation of fibrous tissues) and serious lung damage. Workers in such industries should wear protective masks.