Animal X is cold blooded, has scales and breathe through lungs. It has four-chambered heart. It lays eggs with tough covering, well adapted to dry land conditions. Which of the following animals is being referred to as animal X in the given passage?

Options

A. Chameleon
B. Lizard
C. Crocodile
D. Tortoise

Answer

To determine which animal is being referred to as Animal X, we need to analyze the characteristics provided in the question step by step.

### Step-by-Step Solution:

1. **Identify the Characteristics of Animal X:**
- Cold-blooded
- Has scales
- Breathes through lungs
- Has a four-chambered heart
- Lays eggs with tough covering, adapted to dry land conditions

2. **Understanding Cold-Blooded Animals:**
- Cold-blooded animals, also known as ectothermic animals, cannot regulate their body temperature internally. Their body temperature varies with the environment. Common groups include reptiles, amphibians, and fish.

3. **Identifying the Presence of Scales:**
- Scales are typically found in reptiles and fish. However, since Animal X has lungs and is cold-blooded, we can narrow it down to reptiles.

4. **Breathing Through Lungs:**
- Among the cold-blooded animals, reptiles are known to breathe through lungs, while amphibians have a dual respiratory system (lungs and skin).

5. **Four-Chambered Heart:**
- Most reptiles have a three-chambered heart, but there is an exception. The crocodile is the only reptile that has a four-chambered heart, similar to birds and mammals.

6. **Eggs with Tough Covering:**
- Reptiles lay eggs with tough, leathery shells that are well-adapted to dry land conditions, which aligns with the description of Animal X.

7. **Conclusion:**
- Considering all the characteristics, the only animal that fits all the criteria is the **crocodile**.

### Final Answer:
Animal X is a **crocodile**.