The correct option is A Occupational respiratory disorders
People employed in industries that involve grinding and stone breaking are often prone to suffer from occupational respiratory disorders. This can lead to fibrosis, and cause serious lung damage. Hence, people working in this type of industries should wear protective masks at work.
Pneumonia is caused by bacterial infection and leads to serious respiratory problems.
Emphysema is a chronic disorder in which alveolar walls are damaged due to which respiratory surface is decreased. One of the major causes of this is cigarette smoking.
Asthma is difficulty in breathing due to inflammation of bronchi and bronchioles.