Living fossils of gymnosperms are

Options

A. Cycas
B. Metasequoia
C. Ginkgo biloba
D. All of these

Answer

**Step-by-Step Solution:**

1. **Understanding Gymnosperms**:
- Gymnosperms are a group of seed-producing plants that have seeds that are not enclosed in an ovary. This means their seeds are exposed or "naked."
- Common characteristics of gymnosperms include the presence of cones and needle-like leaves.

2. **Identifying Living Fossils**:
- A "living fossil" refers to a species that has remained relatively unchanged over a long period of geological time and has few or no close relatives.
- These species often represent ancient lineages that have survived through significant changes in the environment.

3. **Examples of Living Fossils in Gymnosperms**:
- The question provides options: Cycas, Metasequoia, and Ginkgo biloba.
- Cycas and Ginkgo biloba are both examples of gymnosperms that are often referred to as living fossils.

4. **Correct Answer**:
- Among the options given, Ginkgo biloba is widely recognized as a living fossil because it has existed for millions of years with little change.
- Therefore, the correct answer to the question "Living fossils of gymnosperms are" is Ginkgo biloba.

5. **Conclusion**:
- While Cycas and Metasequoia can also be considered ancient plants, Ginkgo biloba is the most prominent example of a living fossil among gymnosperms.

**Final Answer**: Ginkgo biloba is the living fossil of gymnosperms.

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