Which of the following pairs are not related?

Options

A. Mendel in Pisum sativum
B. Morgan in Drosophila
C. Bentham and Hooker in binomial nomenclature
D. Hugo de Vries in Oenothera /amarckiana

Answer

To determine which of the following pairs are not related, we will analyze each option provided in the question.

### Step-by-Step Solution:

1. **Analyze the First Option: Mendel in Pisum sativum**
- Gregor Mendel is known for his foundational work in genetics, particularly through his experiments with the pea plant, scientifically named Pisum sativum.
- **Conclusion**: This pair is related.

2. **Analyze the Second Option: Morgan and Drosophila**
- Thomas Hunt Morgan conducted extensive research on Drosophila melanogaster (fruit fly) and made significant contributions to the understanding of genetics and sex-linked traits.
- **Conclusion**: This pair is related.

3. **Analyze the Third Option: Bentham and Hooker in Binomial Nomenclature**
- George Bentham and Joseph Dalton Hooker were botanists known for their work in plant taxonomy. However, the system of binomial nomenclature was actually developed by Carl Linnaeus.
- **Conclusion**: This pair is **not related** as Bentham and Hooker did not create binomial nomenclature.

4. **Analyze the Fourth Option: Hugo de Vries and Oenothera lamarckiana**
- Hugo de Vries is recognized for his work on mutations and studied the plant Oenothera lamarckiana (evening primrose), which is significant in the study of genetics.
- **Conclusion**: This pair is related.

### Final Answer:
The pair that is **not related** is **Bentham and Hooker in Binomial Nomenclature**.

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