Which one of the following sets of animals share a four chambered heart?

Options

A. Amphibian, Reptiles, Birds
B. Crocodiles, Birds, Mammals
C. Crocodiles, Lizards, Turtles
D. Lizards, Mammals, Birds

Answer

To determine which set of animals share a four-chambered heart, we need to analyze the heart structure of the animals in each option provided.

### Step-by-Step Solution:

1. **Understand Heart Structures**:
- A four-chambered heart consists of two atria (auricles) and two ventricles, allowing for complete separation of oxygenated and deoxygenated blood. This is found in birds and mammals.
- A three-chambered heart has two atria and one ventricle, which is typical in amphibians and most reptiles (with the exception of crocodiles).

2. **Examine Each Option**:
- **Option 1: Amphibians, Reptiles, and Birds**:
- Amphibians (like frogs) have a three-chambered heart.
- Reptiles (most, excluding crocodiles) also have a three-chambered heart.
- Birds have a four-chambered heart.
- **Conclusion**: Not all have a four-chambered heart.

- **Option 2: Crocodiles, Birds, and Mammals**:
- Crocodiles have a four-chambered heart.
- Birds have a four-chambered heart.
- Mammals have a four-chambered heart.
- **Conclusion**: All have a four-chambered heart.

- **Option 3: Crocodiles, Lizards, and Turtles**:
- Crocodiles have a four-chambered heart.
- Lizards have a three-chambered heart.
- Turtles also have a three-chambered heart.
- **Conclusion**: Not all have a four-chambered heart.

- **Option 4: Lizards, Mammals, and Birds**:
- Lizards have a three-chambered heart.
- Mammals have a four-chambered heart.
- Birds have a four-chambered heart.
- **Conclusion**: Not all have a four-chambered heart.

3. **Final Conclusion**:
- The only option where all animals have a four-chambered heart is **Option 2: Crocodiles, Birds, and Mammals**.

### Answer:
The correct answer is **Option 2: Crocodiles, Birds, and Mammals**.