__________ is a highly dense ball made of elements such as ion and nickel.

Options

A. Core
B. Mantle
C. Crust
D. Continental curst

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for a specific term that describes a highly dense ball made of elements such as iron and nickel.

2. **Identifying Earth’s Structure**: To answer this, we need to consider the structure of the Earth. The Earth is composed of several layers: the crust, mantle, outer core, and inner core.

3. **Analyzing the Layers**:
- **Crust**: This is the outermost layer and is relatively thin compared to the other layers. It does not contain a high density of iron and nickel.
- **Mantle**: This layer is beneath the crust and is primarily made up of molten rock (magma). It is also not primarily composed of iron and nickel.
- **Outer Core**: This layer is liquid and consists mainly of iron and nickel, but it is not the densest part of the Earth.
- **Inner Core**: This is the innermost layer of the Earth. It is solid and composed mostly of iron and nickel, making it the densest part of the Earth.

4. **Conclusion**: Based on the analysis, the correct answer to the question is "core," specifically referring to the inner core, which is a highly dense ball made of iron and nickel.

**Final Answer**: The answer is **core**.

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