Human and dog is an example of:

Options

A. Internal fertilisation
B. External fertilisation
C. Both of these
D. None of these

Explanation

**Step-by-Step Solution:**

1. **Identify the Organisms**: The question asks about humans and dogs. Both of these organisms are classified as mammals.

2. **Understand Reproductive Methods**: In mammals, reproduction occurs through sexual reproduction, which involves the fusion of male and female gametes.

3. **Define Gametes**: Male gametes (sperm) and female gametes (eggs) are produced by the respective sexes. In the case of humans and dogs, the male gamete is produced by the male and the female gamete is produced by the female.

4. **Fertilization Process**: In mammals, fertilization occurs internally. This means that the male gametes are deposited inside the female's body, where they can meet and fuse with the female gametes.

5. **Conclusion**: Since both humans and dogs exhibit internal fertilization, the correct answer to the question is "internal fertilization".

**Final Answer**: Human and dog is an example of internal fertilization.

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