A condition in which a person's airways become inflamed, narrow, swell and produce extra mucus, which makes it difficult to breathe is known as

1. Asthma
2. Emphysema
3. Chronic bronchitis
4. Chronic obstructive pulmonary disease
Subtopic:  Respiratory Disorders: Part 1 | Respiratory Disorders: Part 2 |
 65%
Level 2: 60%+
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