Hearth of frog is

Options

A. two-chambered
B. three-chambered
C. Four-chambered
D. Six-chambered

Explanation

### Step-by-Step Solution:

1. **Identify the Classification of the Frog**:
- Frogs belong to the class Amphibia. This classification is important because it helps us understand the general characteristics of their anatomy, including their heart structure.

2. **Understand the Heart Structure in Amphibians**:
- Amphibians, including frogs, have a three-chambered heart. This means that their heart consists of two atria (auricles) and one ventricle.

3. **Describe the Components of the Heart**:
- In the three-chambered heart of a frog:
- There are **two auricles**: These receive blood from the body and lungs.
- There is **one ventricle**: This pumps blood out to the body and lungs.

4. **Compare with Other Classes**:
- It is also important to note that while amphibians have a three-chambered heart, reptiles typically have the same; however, crocodiles are an exception as they possess a four-chambered heart.
- Birds (aves) and mammals also have a four-chambered heart, which is more efficient for separating oxygenated and deoxygenated blood.

5. **Conclude the Answer**:
- Therefore, the heart of a frog is classified as a **three-chambered heart**.

### Final Answer:
The heart of a frog is a **three-chambered heart**.

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