Ichthyosaurs are

Options

A. Large marine reptiles which are presently found in oceans
B. Large marine reptiles which are extinct
C. Large marine fishes which are presently found in oceans
D. Large marine fishes which are extinct

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks about Ichthyosaurs and provides four options regarding their classification.

2. **Identifying Ichthyosaurs:**
Ichthyosaurs are known to be a group of reptiles that lived during the Mesozoic era. They are not fishes but are often confused with marine animals due to their aquatic lifestyle.

3. **Evaluating the Options:**
- **Option 1:** "Large marine reptiles which are presently found in the oceans."
- This is incorrect because Ichthyosaurs are extinct and not found in today's oceans.

- **Option 2:** "Large marine reptiles which are extinct."
- This is correct. Ichthyosaurs are indeed large marine reptiles that are now extinct.

- **Option 3:** "Large marine fishes which are presently found in oceans."
- This is incorrect as Ichthyosaurs are reptiles and not fishes, and they are not currently found in the oceans.

- **Option 4:** "Large marine fishes which are extinct."
- This is also incorrect for the same reason as option 3; Ichthyosaurs are not fishes.

4. **Conclusion:**
Based on the evaluation of the options, the correct answer is **Option 2: Large marine reptiles which are extinct.**

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