Select the option which shows viviparous animals only.

Options

A. Lizard, Turtle
B. Platypus, Crocodile
C. Cow, Crocodile
D. Whale, Mouse

Explanation

To solve the question of selecting the option that shows viviparous animals only, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Viviparous Animals**:
- Viviparous animals are those that give birth to live young ones instead of laying eggs. The development of the zygote occurs inside the female's body, providing a safer environment for the developing offspring.

2. **Identify Characteristics of Viviparous Animals**:
- The key characteristic is that the female gives birth to fully developed young ones after a gestation period, which is different from oviparous animals that lay eggs.

3. **Evaluate the Given Options**:
- **Option 1: Lizard and Turtle**:
- Lizard is oviparous (lays eggs), while turtle is viviparous. This option is incorrect as it contains an oviparous animal.
- **Option 2: Platyhelminthes and Crocodile**:
- Crocodile is oviparous (lays eggs). This option is also incorrect as it contains an oviparous animal.
- **Option 3: Cow and Crocodile**:
- Cow is viviparous (gives birth to live young), but crocodile is oviparous. This option is incorrect as well.
- **Option 4: Whale and Mouse**:
- Both whale and mouse are viviparous animals. They give birth to live young ones after developing the zygote inside their bodies.

4. **Select the Correct Option**:
- Based on the evaluation, the only option that contains viviparous animals only is **Option 4: Whale and Mouse**.

### Final Answer:
The correct option that shows viviparous animals only is **Option 4: Whale and Mouse**.

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