Hiccough (hiccup) is due to acitivty of

Options

A. Intercostal muscle
B. Food in air tract
C. Diaphragm
D. Inadequate oxygne in environment

Answer

### Step-by-Step Solution:

1. **Understanding Hiccups**: Hiccups, also known as singultus, are involuntary contractions of the diaphragm muscle.

2. **Identifying the Role of the Diaphragm**: The diaphragm is a dome-shaped muscle located at the base of the thoracic cavity. It plays a crucial role in respiration by contracting and relaxing to help draw air into the lungs.

3. **Mechanism of Hiccups**: During a hiccup, the diaphragm undergoes sudden and involuntary contractions. This is often caused by irritation or stimulation of the phrenic nerve, which controls the diaphragm.

4. **Effect on Vocal Cords**: When the diaphragm contracts, it causes a quick intake of breath. Simultaneously, the opening between the vocal cords (the glottis) closes rapidly, which produces the characteristic "hic" sound.

5. **Conclusion**: Based on the above explanation, hiccups are primarily due to the activity of the diaphragm.

### Final Answer:
Hiccups are due to the activity of the diaphragm.