Our universe is expanding. This speculation is propounded by:

Options

A. Newton
B. Galileo
C. Edwin Hubble
D. Copernicus

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks who proposed the idea that our universe is expanding.

2. **Analyzing the Options**: We have four options to consider:
- A) Newton
- B) Galileo
- C) Edwin Hubble
- D) Corporal Nikas

3. **Identifying Key Historical Figures**:
- **Newton**: Known for laws of motion and universal gravitation, but not for the expansion of the universe.
- **Galileo**: Made significant contributions to astronomy but did not propose the expansion of the universe.
- **Edwin Hubble**: In 1920, he observed that galaxies are moving away from the Milky Way, leading to the conclusion that the universe is expanding.
- **Corporal Nikas**: Not a recognized figure in the context of the universe's expansion.

4. **Conclusion**: Based on the analysis, Edwin Hubble is the correct answer as he was the one who proposed the idea of an expanding universe.

5. **Final Answer**: The speculation that our universe is expanding is propounded by Edwin Hubble.

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