. Which naturalist had said that evolution of life occurred by use and disuse of organs?

Options

A. Louis Pasteur
B. de Vries
C. Lamarck
D. Darwin

Explanation

**Step-by-Step Text Solution:**

1. **Identify the Naturalist**: The question asks for a naturalist who proposed a theory regarding the evolution of life based on the use and disuse of organs.

2. **Recall the Theory**: The theory of use and disuse suggests that organisms can develop or lose traits based on their usage. If an organ is used frequently, it becomes stronger or more developed, while organs that are not used may become weaker or even disappear over generations.

3. **Connect to the Naturalist**: The naturalist who is most famously associated with this theory is Jean-Baptiste Lamarck.

4. **Provide Examples**: Lamarck illustrated his theory with examples:
- **Giraffes**: He suggested that ancestral giraffes had shorter necks, but as they stretched their necks to reach higher leaves, their necks gradually became longer over generations due to the use of this organ.
- **Snakes**: He proposed that snakes once had legs, but as they adapted to a lifestyle without the use of legs, these limbs became vestigial and eventually disappeared.

5. **Conclude**: Therefore, the correct answer to the question is Jean-Baptiste Lamarck, as he was the naturalist who proposed that evolution occurred through the use and disuse of organs.

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