Complete mineralisation of original structures results in

Options

A. Unaltered fossils
B. Petrified fossils
C. Moulds
D. Casts

Answer

**Step-by-Step Solution:**

1. **Understanding Fossils**: Fossils are the preserved remains or traces of organisms that lived in the past. They can be formed from hard parts like bones, shells, and teeth.

2. **Types of Fossils**: There are different types of fossils, including unaltered fossils, petrified fossils, molds, and casts. Each type has distinct characteristics based on the preservation process.

3. **Unaltered Fossils**: These fossils retain the original material of the organism, meaning they are preserved in the same form as when the organism was alive.

4. **Petrified Fossils**: This type of fossil forms through a process called petrification, where the organic material of the organism is replaced by inorganic minerals. This process leads to the complete mineralization of the original structure.

5. **Molds and Casts**: Molds are impressions left by the fossil when the surrounding material hardens. If these impressions are later filled with minerals, they form a cast.

6. **Conclusion**: Given the question about complete mineralization of original structures, the correct answer is "petrified fossil," as this process involves the replacement of organic material with inorganic minerals.

**Final Answer**: Complete mineralization of original structures results in **petrified fossils**.

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