Assertion : Fertilisation which takes place inside the female body is called internal fertilisation.
Reason: Internal fertilisation is very common in aquatic animals such as starfish.

Options

A. Both Assertion and Reason are true and Reason is correct explanation of the assertion.
B. Both Assertion and Reason are true but Reason is not the correct explanation of the assertion.
C. Assertion is true but Reason is false.
D. Assertion is false but Reason is true.

Explanation

To solve the question, we need to analyze both the assertion and the reason provided.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Fertilisation which takes place inside the female body is called internal fertilisation."
- This statement is true. Internal fertilisation occurs when the male gamete fertilizes the female gamete inside the female's body.

2. **Understanding the Reason**:
- The reason states that "Internal fertilisation is very common in aquatic animals such as starfish."
- This statement is false. Starfish, which are aquatic animals, typically undergo external fertilisation, where gametes are released into the water for fertilisation to occur outside the body.

3. **Conclusion**:
- Since the assertion is true and the reason is false, we conclude that the correct answer is that the assertion is true, but the reason is false.

### Final Answer:
The assertion is true, and the reason is false.

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