Oldest fossils of land animals consists of

Options

A. Amphibians
B. Centipedes
C. Primitive spider
D. Both B and C

Answer

To answer the question about the oldest fossils of land animals, we will analyze the options provided and determine which organisms are considered the earliest known terrestrial animals.

### Step-by-Step Solution:

1. **Understanding the Options**:
- The options provided include amphibians, centipedes, and primitive spiders.
- We need to identify which of these groups contains the oldest fossils of land animals.

2. **Analyzing Amphibians**:
- Amphibians are a class of animals that can live both in water and on land.
- They evolved later than some of the earliest terrestrial animals, so they are not the correct answer.

3. **Examining Centipedes**:
- Centipedes belong to the class of arthropods and are known to be among the earliest terrestrial animals.
- Fossils of centipedes date back to the Silurian period, making them one of the oldest known land-dwelling organisms.

4. **Considering Primitive Spiders**:
- Primitive spiders also belong to the arachnids and are considered early terrestrial animals.
- Similar to centipedes, the fossils of primitive spiders date back to the same geological periods.

5. **Conclusion**:
- Both centipedes and primitive spiders are recognized as some of the oldest fossils of land animals.
- Therefore, the correct answer is that the oldest fossils of land animals consist of both centipedes and primitive spiders.

### Final Answer:
The oldest fossils of land animals consist of **centipedes and primitive spiders**.

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