Assertion : The sustaining surface for the gliding in certain animals, is a fold or series of folds of the skin known as patagium .
Reason : The gliding flights are performed by erboreal animals.

Options

A. If both the assertion and reason are true statement and reason is correct explanation of the assertion .
B. If both the assertion and reason are true statement but reason is not a correct explanation of the assertion .
C. If the assertion is true but the reason is a false statement.
D. If both assertion and reason are false statements.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that the patagium is a fold or series of folds of skin that serves as a sustaining surface for gliding in certain animals. This is true. The patagium is indeed a membranous structure that aids in gliding, found in animals such as bats, flying squirrels, and flying lizards.

2. **Understanding the Reason**: The reason provided states that gliding flights are performed by arboreal animals. Arboreal animals are those that primarily live in trees. While some arboreal animals may glide, not all of them do. Gliding is a specific form of movement that is not exclusive to arboreal animals.

3. **Evaluating the Truth of Both Statements**:
- The assertion is true because the patagium does function as a gliding surface.
- The reason is false because it inaccurately generalizes that all gliding flights are performed by arboreal animals. Not all gliders are arboreal; for example, flying fish glide over water.

4. **Conclusion**: Since the assertion is true and the reason is false, the correct answer is that the assertion is true, but the reason is false.

**Final Answer**: The correct option is that the assertion is true, but the reason is false.

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