First chemical identification of auxin, indole 3-acetic acid, was carried out by

Options

A. Went
B. Thimann
C. Darwin
D. Paal.

Answer

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

1. **Understanding Auxins**: Auxins are a class of plant hormones that play a significant role in the growth and behavioral processes of plants. The most common auxin is indole-3-acetic acid (IAA).

2. **Identifying Key Scientists**: The question asks about the first chemical identification of auxin. Several scientists contributed to the understanding of auxins, including Frits Warmold Wendt, Kenneth V. Thiemann, Charles Darwin, and Pahl.

3. **Role of Frits Warmold Wendt**: Wendt was the first to describe the role of auxins in plant growth. However, he did not perform the chemical identification of indole-3-acetic acid.

4. **Role of Kenneth V. Thiemann**: Thiemann was crucial in the first isolation of a phytohormone and in determining the chemical structure of indole-3-acetic acid. Therefore, he is the scientist who conducted the first chemical identification of auxin.

5. **Evaluating Other Options**: Charles Darwin and Pahl contributed to the discovery of auxins but did not perform any chemical identification. Thus, their options are incorrect.

6. **Conclusion**: The correct answer to the question is Kenneth V. Thiemann, as he was the first to chemically identify indole-3-acetic acid.

**Final Answer**: Kenneth V. Thiemann

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