As we go higher up on mountains, our ears pop because .

Options

A. Air pressure outside our ears increases
B. The pressure exerted by the blood near ears increases
C. Air pressure outside our ears decreases.
D. None of these

Answer

To solve the question regarding why our ears pop as we go higher up on mountains, we can break it down into a few steps:

### Step 1: Understanding Atmospheric Pressure
- At sea level, the atmospheric pressure is higher due to the weight of the air above us. As we ascend to higher altitudes, such as on a mountain, the amount of air above us decreases, leading to a decrease in atmospheric pressure.

### Step 2: Pressure Inside and Outside the Ear
- The human ear has an internal pressure that is usually balanced with the external atmospheric pressure. When we are at a lower altitude, the pressure inside our ear is equal to the atmospheric pressure outside.

### Step 3: Ascending to Higher Altitudes
- As we climb higher, the external atmospheric pressure decreases. However, the pressure inside our ear does not decrease at the same rate immediately. This creates a pressure imbalance between the inside and outside of the ear.

### Step 4: The Ear Popping Sensation
- To equalize this pressure difference, the Eustachian tube (which connects the middle ear to the back of the throat) opens, allowing air to flow in or out. This sudden movement of air can cause a popping sound or sensation in the ears.

### Conclusion
- Therefore, the reason our ears pop when we go higher up on mountains is that the air pressure outside our ears decreases as we ascend, leading to a pressure imbalance that our body tries to equalize.

### Final Answer
- Our ears pop because the air pressure outside our ears decreases as we go higher up on mountains.

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