Select the incorrect option regarding snakes.

Options

A. They have thin muscles that are connected to each other.
B. They are invertebrates.
C. During movement, the snake's body curves into many loops.
D. Backbone and ribs of snakes help them to move.

Explanation

**Step-by-Step Solution:**

1. **Identify the Options**: The question asks to select the incorrect option regarding snakes. We need to analyze each option provided.

2. **Analyze the First Option**: The first option states that snakes have thin muscles that are connected to each other. This statement is correct because snakes do have muscles that are interconnected, allowing for flexibility and movement.

3. **Analyze the Second Option**: The second option claims that snakes are invertebrates. This statement is incorrect. Snakes belong to the class Reptilia and are classified under the phylum Chordata, which means they have a backbone (vertebrate). Therefore, this option is the incorrect one.

4. **Analyze the Third Option**: The third option mentions that during movement, a snake's body curves into many loops. This is a correct statement as snakes use their flexible bodies to create loops for movement and to sense vibrations.

5. **Analyze the Fourth Option**: The fourth option states that the backbone and ribs of the snake help them to move. This is also correct since snakes have a prominent and flexible vertebral column that aids in their locomotion.

6. **Conclusion**: After analyzing all the options, we conclude that the second option is the incorrect one, as snakes are vertebrates, not invertebrates.

**Final Answer**: The incorrect option regarding snakes is the second option, which states that they are invertebrates.

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