If a particular animal has shelled eggs, hair and teats on the body and has cloaca, it may be a connecting link between :

Options

A. Reptiles and birds
B. Birds and mammals
C. Reptiles and mammals
D. None of them

Answer

To solve the question, we need to analyze the characteristics of the animal described and determine which groups it could potentially connect.

### Step-by-Step Solution:

1. **Identify the Characteristics**: The animal in question has shelled eggs, hair, teats, and a cloaca.
- **Shelled Eggs**: This indicates that the animal is oviparous (lays eggs).
- **Hair and Teats**: These features are typically associated with mammals.
- **Cloaca**: This is a single opening for excretion and reproduction, commonly found in reptiles and some mammals.

2. **Evaluate the Options**:
- **Option 1: Reptiles and Birds**:
- Reptiles lay shelled eggs, and birds also lay eggs. However, birds do not have hair or teats. Thus, this option is incorrect.

- **Option 2: Birds and Mammals**:
- Birds lay shelled eggs, but they do not have hair or teats. Therefore, this option is also incorrect.

- **Option 3: Reptiles and Mammals**:
- Reptiles lay shelled eggs and have cloacas. Mammals have hair and teats. An animal with characteristics of both reptiles (shelled eggs, cloaca) and mammals (hair, teats) could serve as a connecting link between these two groups. This option is correct.

- **Option 4: None of the Above**:
- Since we have identified option 3 as correct, this option is incorrect.

3. **Conclusion**: The animal described is a connecting link between reptiles and mammals due to its unique combination of characteristics.

### Final Answer:
The animal may be a connecting link between **Reptiles and Mammals**.