Cell phones use radio waves for communications. what layer of the atmosphere aids in reflecting the radio waves? the mesosphere the stratosphere the troposphere the thermosphere

Option (4)

Explanation:

The thermosphere is the layer in the atmosphere that protects the earth as well as helps in carrying the radio signals used for communication purposes. It is the region that lies between the mesosphere (below) and the exosphere (above).  

In this layer, the radio waves are used as a medium for communication. These radio waves carry the data or signals in the form of magnetic fields as well as the oscillating electric field, which are commonly considered as the electromagnetic field (EMF). These radio waves carrying information travels at a speed of light in the air, transmitting these waves in every direction.

Thus, the correct answer is option (4).

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