Prollen grains are well preserved as fossils because of the presence of:

Options

A. sporopollenin
B. cellulose
C. pectin
D. carotenoids

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks why pollen grains are well preserved as fossils. This indicates we need to identify the specific component in pollen grains that contributes to their preservation.

2. **Identifying the Components of Pollen Grains**: Pollen grains have a unique structure consisting of two layers: the outer layer called the exine and the inner layer called the intine.

3. **Examining the Layers**:
- The **exine** is the outer layer and is known for its durability. It is primarily composed of a substance called **sporopollenin**.
- The **intine** is the inner layer, which is softer and made up of pectocellulose.

4. **Properties of Sporopollenin**: Sporopollenin is recognized as one of the most resistant organic materials. It can withstand extreme environmental conditions, including high temperatures and strong acids. This resistance is crucial for the preservation of pollen grains over geological time.

5. **Conclusion**: Given that sporopollenin is the component that provides durability and resistance to degradation, it is the reason why pollen grains are well preserved as fossils.

**Final Answer**: Pollen grains are well preserved as fossils because of the presence of **sporopollenin**.

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