The extreme specialization and extinction of great reptiles occurred in `:`

Options

A. Permian
B. Triassic
C. Jurassic
D. Cretaceous

Answer

To answer the question regarding the extreme specialization and extinction of great reptiles, we will follow these steps:

### Step-by-Step Solution:

1. **Understand the Mesozoic Era**:
- The Mesozoic Era is a significant geological time period that occurred before 180 million years ago. It is often referred to as the "Age of Reptiles" or the "Golden Age of Reptiles."

2. **Identify the Three Periods of the Mesozoic Era**:
- The Mesozoic Era is divided into three main periods:
- **Triassic Period**: This is when reptiles originated.
- **Jurassic Period**: This period is characterized by the specialization of reptiles.
- **Cretaceous Period**: This period is marked by both the specialization and extinction of great reptiles.

3. **Determine the Focus of the Question**:
- The question specifically asks about the extreme specialization and extinction of great reptiles.

4. **Analyze Each Period**:
- **Triassic Period**: This is primarily known for the origin of reptiles, not specialization or extinction.
- **Jurassic Period**: While specialization occurs, there is no significant extinction of reptiles during this time.
- **Cretaceous Period**: This period is noted for both the specialization of reptiles and the extinction of many species, including dinosaurs.

5. **Conclude with the Correct Answer**:
- Based on the analysis, the extreme specialization and extinction of great reptiles occurred in the **Cretaceous Period**.

### Final Answer:
The extreme specialization and extinction of great reptiles occurred in the **Cretaceous Period**.

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