When a hen reproduces, a zygote is formed through _________ fertilization, which does not happen in frogs or fish.

Options

A. Internal
B. External
C. Both (a) and (b)
D. None of them

Answer

**Step-by-Step Solution:**

1. **Understanding the Types of Fertilization**: There are two main types of fertilization in animals: internal and external. Internal fertilization occurs inside the female's body, while external fertilization occurs outside, typically in water.

2. **Identifying the Process in Hens**: Hens reproduce through internal fertilization. In this process, the male hen (rooster) mates with the female hen (hen) to transfer sperm, which fertilizes the eggs inside the hen's body.

3. **Formation of the Zygote**: After fertilization occurs internally, a zygote is formed. This zygote then develops into an egg, which is laid by the hen.

4. **Comparing with Frogs and Fish**: In contrast, frogs and fish reproduce through external fertilization. In these animals, the female lays eggs in water, and the male releases sperm over them, leading to fertilization occurring outside of the female's body.

5. **Conclusion**: Therefore, the correct answer to the question is that a zygote is formed through **internal** fertilization in hens, which does not happen in frogs or fish.

**Final Answer**: When a hen reproduces, a zygote is formed through **internal** fertilization, which does not happen in frogs or fish.

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