The layer of atmosphere between 10 km to 50 km above the sea level is called as:
A) Troposphere
B) Mesosphere
C) Stratosphere
D) Thermosphere

Hint: We live in the troposphere layer of the atmosphere which extends to 6.2 miles. Just above the troposphere layer, the stratosphere starts which extends to 31 miles high. Then the mesosphere comes, which extends to 85 kilometres high and then comes the thermosphere which extends to 600 kilometres.

Complete step by step solution:
The earth’s atmosphere has a series of layers. These are:
- Troposphere: This layer is the lowermost layer of the atmosphere. It starts at the earth’s surface and extends upward to about 10 km (6.2 miles). We humans live in this layer and nearly all weather occurs in this layer.
- Stratosphere: The next layer after the troposphere is stratosphere. It extends from the top of the troposphere (i.e., 10 km) to about 50 km above the sea level. The ozone layer is found within this layer.
- Mesosphere: Above the stratosphere is mesosphere. It extends upward to about 85 km above the planet. Most meteors burn up in the mesosphere layer
- Thermosphere: The layer of very rare air above the mesosphere is called thermosphere. Many satellites actually orbit around the earth within this layer.
Thus, the layer of atmosphere which is between 10 km to 50 km above the sea level is called the stratosphere.

Hence, option C is the correct answer.

Note: There are two more layers above the thermosphere which are found. These are the exosphere and ionosphere. An interesting fact to note is that ozone molecules in the stratosphere layer absorb high-energy ultraviolet (UV) radiation from the sun and convert the UV energy into heat.