Egyptian pyramids are made of rocks formed from

Options

A. (a) nasal deposits of sea birds
B. (b) silica deposits of radiolarians
C. (c) limestone deposits of foraminiferan shells
D. (d) diatomaceous earth

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the material composition of the Egyptian pyramids, specifically what type of rocks they are made from.

2. **Historical Context**: The Egyptian pyramids, particularly the Great Pyramid of Giza, were built during the reign of Pharaoh Khufu around 2500-2560 BC. This gives us a timeframe for the construction and the materials used.

3. **Composition of the Pyramids**: Research indicates that the Great Pyramid of Giza was constructed using over 5 million blocks of limestone and a significant amount of granite, approximately 80 tons.

4. **Analyzing the Options**: The options provided are:
- A) Nasal deposits of seabirds
- B) Silica deposits
- C) Limestone deposits of foraminiferan shells
- D) Diatomaceous earth

5. **Evaluating Each Option**:
- **Option A** (Nasal deposits of seabirds): This is incorrect as it does not relate to the materials used in pyramid construction.
- **Option B** (Silica deposits): This is also incorrect as it does not match the known composition of the pyramids.
- **Option C** (Limestone deposits of foraminiferan shells): This is the correct answer, as limestone is indeed composed of foraminiferan shells and was a primary material used in the pyramids.
- **Option D** (Diatomaceous earth): This option is incorrect as it does not pertain to the construction materials of the pyramids.

6. **Conclusion**: After evaluating all options, the correct answer is **C) Limestone deposits of foraminiferan shells**.

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