Which of these animals follows internal fertilization?

Options

A. Frog
B. Shark
C. Sea horse
D. Kingfisher

Answer

To determine which of the given animals undergo internal fertilization, we can analyze each option based on the definition of internal fertilization.

**Step 1: Understand Internal Fertilization**
- Internal fertilization occurs when the sperm and egg meet inside the female's body. This process leads to the development of a zygote within the female.

**Step 2: Analyze Each Option**
1. **Frog**: Frogs reproduce by external fertilization. The female lays eggs in water, and the male releases sperm over the eggs, leading to fertilization outside the female's body.

2. **Shark**: Sharks are known for internal fertilization. The male shark uses a specialized organ called a clasper to insert sperm into the female's cloaca, where fertilization occurs internally.

3. **Seahorse**: Seahorses also do not follow internal fertilization. The female deposits her eggs into the male's brood pouch, where the male then fertilizes them. This process is considered external fertilization since the fertilization occurs in the pouch, which is not inside the female's body.

4. **Kingfisher**: Like many birds, kingfishers reproduce through internal fertilization. The male and female mate, and fertilization occurs inside the female's body.

**Step 3: Conclusion**
Based on the analysis:
- The animals that undergo internal fertilization are **Shark** and **Kingfisher**.

**Final Answer**: Shark and Kingfisher follow internal fertilization.

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