When an aeroplane takes off, some occupants, often feel pain in the region of ears. This is because of

Options

A. rapid movement of fluid in semicircular canals
B. blockage of eustachian tubes
C. rapid movements of otoliths in macula region of utricle and saccule
D. increased amplitude of the vibrating tympanum due to very loud sound produced by the jet engines

Answer

### Step-by-Step Solution:

1. **Understanding the Context**: When an airplane takes off, it experiences a rapid change in altitude, which affects the air pressure inside and outside the aircraft.

2. **Middle Ear Anatomy**: The middle ear contains a cavity filled with air and is connected to the throat by the Eustachian tube. This tube helps equalize the pressure between the middle ear and the external environment.

3. **Pressure Changes During Takeoff**: As the airplane ascends, the external air pressure decreases rapidly. However, the pressure in the middle ear does not adjust as quickly, leading to a pressure difference.

4. **Effect of Pressure Difference**: The increase in external air pressure causes a relative decrease in pressure within the middle ear cavity. This pressure difference creates discomfort.

5. **Eustachian Tube Function**: Normally, the Eustachian tube opens to allow air to flow into the middle ear, equalizing the pressure. However, if the tube is blocked or does not function properly, air cannot enter the middle ear.

6. **Resulting Pain**: The blocked Eustachian tube leads to a build-up of pressure on the eardrum, causing it to push inward. This pressure on the eardrum results in pain, which is commonly felt by passengers during takeoff.

7. **Conclusion**: The pain experienced in the ears during an airplane takeoff is primarily due to the blockage of the Eustachian tubes, which prevents the equalization of pressure in the middle ear.

### Final Answer:
The pain in the region of the ears when an airplane takes off is because of the **blockage of Eustachian tubes**, which leads to a pressure difference and discomfort in the middle ear.

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