Asthma is characterised by

Options

A. Spams in bronchial muscle
B. Alveolar wall degradation
C. Pain in lungs
D. Damage in diaphragm

Answer

**Step-by-Step Solution:**

1. **Understanding Asthma**: Asthma is a chronic respiratory condition that primarily affects the lungs. It is characterized by inflammation and narrowing of the airways, which can lead to difficulty in breathing.

2. **Identifying Symptoms**: The main symptoms of asthma include wheezing, coughing, shortness of breath, and chest tightness. These symptoms arise due to spasms in the bronchial muscles and increased mucus production.

3. **Evaluating the Options**:
- **Option 1: Spasm in bronchial muscle**: This is a characteristic of asthma. The bronchial muscles can spasm, leading to constriction of the airways.
- **Option 2: Alveolar wall degradation**: This is incorrect. Asthma primarily affects the bronchi and bronchioles, not the alveoli.
- **Option 3: Pain in lungs**: This is misleading. While asthma can cause discomfort in the chest, it is not characterized by pain in the lungs specifically.
- **Option 4: Damage in diaphragm**: This is also incorrect. The diaphragm is not directly affected by asthma; the primary issue lies within the lungs and airways.

4. **Conclusion**: Based on the evaluation, the correct characteristic of asthma is the spasm in bronchial muscle. Therefore, the right answer is **Option A**.