The most highly advanced character in crocodile (Reptilia) is the presence of

Options

A. Powerful jaws
B. Shelled eggs
C. Pleurodont dentition
D. Four-chambered

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:** The question asks for the most advanced character found in crocodiles, which belong to the class Reptilia.

2. **Evaluating the Options:**
- **Powerful Jaws:** While crocodiles do have powerful jaws, this characteristic is not unique to them as it is also found in tortoises and other reptiles.
- **Shelled Eggs:** All reptiles, including crocodiles, produce shelled eggs made of calcium carbonate. This feature is common across the reptilian class and does not distinguish crocodiles as more advanced.
- **Pleurodont Dentition:** This type of dentition, where teeth are attached to the jawbone, is also found in other reptiles and is not exclusive to crocodiles.
- **Four-Chambered Heart:** This is a significant feature of crocodiles. Unlike most reptiles, which have a three-chambered heart, crocodiles possess a four-chambered heart, similar to mammals. This advanced circulatory system allows for more efficient oxygenation of blood.

3. **Conclusion:** The most highly advanced character in crocodiles is the presence of a **four-chambered heart**.

---