The loss of strength of a signal while propagating through a medium is known as

Options

A. reception
B. absorption
C. trasnmission
D. attenuation

Explanation

**Step-by-Step Solution:**

1. **Understanding Signal Propagation**: When a signal is transmitted from a transmitter to a receiver, it travels through a medium, which could be air, cables, or optical fibers.

2. **Identifying Signal Loss**: As the signal travels through this medium, it may lose strength due to various factors such as distance, interference, and the properties of the medium itself.

3. **Defining the Term**: The term used to describe the loss of strength of a signal while it is propagating through a medium is known as "attenuation".

4. **Conclusion**: Therefore, the correct answer to the question is that the loss of strength of a signal while propagating through a medium is called attenuation.

**Final Answer**: Attenuation

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