Why does the surface of the planet Mars appear red in colour?

Options

A. Presence of acids in its atmosphere
B. Presence of iron oxide on its surface
C. Presence of dust particles in its atmosphere
D. Presence of water on its surface

Answer

**Step-by-Step Solution:**

1. **Identify the Planet**: The question asks about Mars, which is commonly known as the "Red Planet."

2. **Observation of Color**: Mars appears red when viewed from Earth. This observation is crucial to understanding why it is called the Red Planet.

3. **Investigate the Surface Composition**: To explain the red color, we need to look at what Mars is made of. The surface of Mars contains various minerals and compounds.

4. **Focus on Iron Oxide**: The primary reason for the red appearance of Mars is the presence of iron oxide, commonly known as rust. Iron oxide has a reddish-brown color.

5. **Conclusion**: Since Mars has a significant amount of iron oxide on its surface, this is the reason why it appears red. Therefore, the correct answer to the question is that the presence of iron oxide on Mars' surface gives it its characteristic red color.

6. **Eliminate Incorrect Options**: Other options like the presence of acids, dust particles, or water do not contribute to the red appearance of Mars.

**Final Answer**: The surface of the planet Mars appears red in color due to the presence of iron oxide on its surface.

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