Which of the following is a living fossil?

Options

A. Mirabilis jalapa
B. Gingko biloba
C. Pinus longifolla
D. Dalbergia sissoo

Answer

To determine which of the given options is a living fossil, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Living Fossils**:
- Living fossils are species that have remained relatively unchanged over long periods of geological time and closely resemble their ancient ancestors found in the fossil record.

2. **Examine the Given Options**:
- The options provided are:
- A) Mirabilis Jalapa
- B) Ginkgo Biloba
- C) Pinus Longifolia
- D) Dalbergia Sissu

3. **Identify Known Living Fossils**:
- Some well-known examples of living fossils include:
- Ginkgo Biloba (a tree species)
- Horseshoe Crab
- Sphenodon (tuatara)

4. **Analyze Each Option**:
- **Mirabilis Jalapa**: This is a flowering plant and does not fit the criteria of a living fossil.
- **Ginkgo Biloba**: This tree species is often cited as a classic example of a living fossil due to its ancient lineage and similarity to fossilized specimens.
- **Pinus Longifolia**: This is a type of pine tree and is not considered a living fossil.
- **Dalbergia Sissu**: This is a type of rosewood and does not meet the criteria for living fossils.

5. **Conclusion**:
- Based on the analysis, the correct answer is **B) Ginkgo Biloba**, as it is recognized as a living fossil.

### Final Answer:
**B) Ginkgo Biloba**