Smoking causes ___________.
A) Sinusitis
B) Laryngitis
C) Chronic bronchitis
D) Emphysema
E) Pneumonia
Select the correct option:

Smoking is a major risk factor for respiratory diseases, particularly Chronic Obstructive Pulmonary Disease (COPD).

COPD primarily includes two conditions:
1. Chronic bronchitis: Inflammation of the bronchi, leading to excessive mucus production and chronic cough.
2. Emphysema: Destruction of the alveolar walls, which decreases the respiratory surface area for gas exchange.

Both chronic bronchitis and emphysema are directly caused by long-term smoking.

Therefore, C and D only are correct.

Answer: C and D only