_______ is the progressive decrease of signal strength with increasing distance.

Options

A. Radiation
B. Attenuation
C. Modulation
D. Propagation

Explanation

To solve the question, we need to identify the term that describes the progressive decrease of signal strength with increasing distance. Here’s a step-by-step solution:

### Step 1: Understand the Question
The question asks for a term that describes the decrease in signal strength as the distance increases.

### Step 2: Analyze the Options
The options provided are:
- Radiation
- Attenuation
- Modulation
- Propagation

### Step 3: Define Each Option
1. **Radiation**: This generally refers to the emission of energy as electromagnetic waves or as moving subatomic particles. It does not specifically relate to the decrease in signal strength.

2. **Attenuation**: This term refers to the reduction in the strength of a signal as it travels through a medium. It is commonly used in telecommunications to describe the loss of signal strength over distance.

3. **Modulation**: This is a technique used to encode information onto a carrier wave. It does not refer to the decrease in signal strength.

4. **Propagation**: This term refers to the way in which waves travel through a medium. While it relates to the transmission of signals, it does not specifically address the decrease in signal strength.

### Step 4: Identify the Correct Answer
From the definitions, it is clear that **attenuation** is the correct term that describes the progressive decrease of signal strength with increasing distance.

### Final Answer
The correct answer is **attenuation**.

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