At the time of flight, the pain in the ear is due to

Options

A. Sound of the engine
B. Difference in pressure between the middle and inner ear
C. Difference in pressure between the middle and outer ear
D. Opening of sustachian tube

Answer

### Step-by-Step Solution:

1. **Understanding the Anatomy of the Ear**:
- The ear consists of three main parts: the outer ear, middle ear, and inner ear. The Eustachian tube connects the middle ear to the pharynx and helps equalize pressure.

2. **Recognizing the Problem During Flight**:
- During a flight, especially during takeoff and landing, there is a rapid change in altitude which leads to a change in air pressure.

3. **Effect of Pressure Changes**:
- As the airplane ascends or descends, the air pressure outside the ear changes quickly. The Eustachian tube may not equalize this pressure change immediately.

4. **Pressure Imbalance**:
- When the pressure in the outer ear changes faster than the pressure in the middle ear, a pressure imbalance occurs. This can cause the eardrum to stretch, leading to pain.

5. **Relief Mechanisms**:
- Actions such as swallowing, yawning, or chewing can help open the Eustachian tube, allowing air to flow into the middle ear and equalize the pressure, which alleviates the pain.

6. **Identifying the Correct Option**:
- The pain in the ear during flight is primarily due to the difference in pressure between the middle ear and the outer ear, not due to sound or pressure differences between the middle and inner ear.

### Final Answer:
The pain in the ear at the time of flight is due to the difference in pressure between the middle ear and the outer ear.

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