The growth hormone, Gibberellin, was discovered by

Options

A. Yabuta and Sumiki
B. Dutrochet and Dolk
C. Donoho and Walker
D. Hashimoto and Rappaport.

Answer

**Step-by-Step Solution:**

1. **Identify the Growth Hormone**: The question asks about the growth hormone known as Gibberellin. It is important to recognize that Gibberellin is a type of plant hormone involved in growth processes.

2. **Historical Context**: Gibberellin was discovered in the year 1935. Understanding the historical context helps in identifying the scientists involved in its discovery.

3. **Discoverers of Gibberellin**: The hormone Gibberellin was discovered by two scientists, Yabuta and Tsumugi. They conducted research that led to the isolation of this hormone.

4. **Source of Isolation**: Yabuta and Tsumugi isolated Gibberellin from a fungus known as Gibberella fujikuroi. This information is crucial as it links the hormone to its biological source.

5. **Functions of Gibberellin**: Gibberellin plays various roles in plant growth, including stem elongation, seed germination, and breaking dormancy. This knowledge reinforces the importance of Gibberellin in plant biology.

6. **Conclusion**: Based on the information gathered, the correct answer to the question is that Gibberellin was discovered by Yabuta and Tsumugi.

**Final Answer**: The growth hormone, Gibberellin, was discovered by Yabuta and Tsumugi.

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