Read the following characters :
They have two pairs of limbs
Homoiothermous and heart is four-chambered
Fertilization is internal
Different types of teeth are present in jaw
Above characters belong to -

Options

A. Aves
B. Reptilia
C. Mammalia
D. Amphibia

Answer

To solve the question regarding the characters provided, we will analyze each character step by step and determine which group of animals they belong to.

### Step-by-Step Solution:

1. **Identify the Characters:**
- The characters given are:
- Two pairs of limbs
- Homoiothermous (warm-blooded)
- Heart is four-chambered
- Fertilization is internal
- Different types of teeth are present in the jaw

2. **Analyze Each Character:**
- **Two pairs of limbs:** This suggests that the organism has four limbs, which is characteristic of many tetrapods, including mammals, birds, and some reptiles.
- **Homoiothermous (warm-blooded):** This indicates that the organism can maintain a constant body temperature regardless of the environment. This is a trait of birds and mammals.
- **Heart is four-chambered:** A four-chambered heart is found in birds and mammals, allowing for efficient separation of oxygenated and deoxygenated blood.
- **Fertilization is internal:** This means that fertilization occurs inside the female's body, which is typical of mammals and some reptiles.
- **Different types of teeth are present in the jaw:** This suggests a varied diet, which is common in mammals, as they have specialized teeth for different functions (incisors, canines, molars).

3. **Evaluate the Options:**
- **Option A: Apes**
- Apes are mammals, have two pairs of limbs, are warm-blooded, have a four-chambered heart, and exhibit internal fertilization. They also have different types of teeth. This option fits all the characters.
- **Option B: Reptilia**
- Reptiles typically have a three-chambered heart (except for some advanced reptiles), and they usually lay eggs (external fertilization). This does not match the characters provided.
- **Option C: Mammalia**
- Mammals have all the characteristics mentioned: two pairs of limbs, are warm-blooded, have a four-chambered heart, internal fertilization, and different types of teeth. This option fits perfectly.
- **Option D: Amphibia**
- Amphibians generally have a three-chambered heart and lay eggs in water. They do not match the criteria provided.

4. **Conclusion:**
- Based on the analysis, the characters described belong to the class **Mammalia**.

### Final Answer:
The above characters belong to **Mammalia**.