Starfish and frog 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 mentions two organisms: starfish and frog.

2. **Understand the Reproductive Process**: We need to determine how these organisms reproduce, specifically focusing on the type of fertilization they use.

3. **Fertilization in Starfish**: Starfish reproduce by releasing their gametes (sperm and eggs) into the water. This process occurs outside the female's body, where fertilization takes place.

4. **Fertilization in Frogs**: Frogs also reproduce by external fertilization. The female frog lays eggs in water, and the male frog releases sperm over the eggs to fertilize them, again outside the female's body.

5. **Conclusion**: Since both starfish and frogs use external fertilization, the correct answer to the question is "external fertilization."

6. **Select the Correct Option**: Among the provided options, the correct answer is option number two: external fertilization.

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