A theory proposed to explain observed phenomena is

Options

A. Postulate
B. Hypothesis
C. Law
D. Model

Answer

To answer the question "A theory proposed to explain observed phenomena is," we need to analyze the definitions of the terms involved.

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for a term that describes a theory which is specifically aimed at explaining phenomena that have been observed.

2. **Defining Key Terms**:
- **Theory**: In scientific terms, a theory is a well-substantiated explanation of some aspect of the natural world that is based on a body of evidence and has stood up to repeated testing and scrutiny.
- **Phenomena**: These are observable events or occurrences that can be studied and measured.
- **Model**: A model is a representation of a system or phenomenon that helps explain how it works. It simplifies complex realities to make them easier to understand.

3. **Analyzing the Options**:
- The question implies that the correct answer is a term that encapsulates the idea of explaining observed phenomena.
- A **model** is often used to represent and explain phenomena in a simplified way, making it a suitable candidate for the answer.

4. **Conclusion**: Based on the definitions and analysis, the correct answer to the question is **model**. A model is proposed to explain observed phenomena, making it the most appropriate choice.

### Final Answer:
A theory proposed to explain observed phenomena is a **model**.

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