Mutation theory to explain mechanism of evolution was given by Hugo de Vries and he experimented on the:

Options

A. Garden pea
B. Fruit fly
C. China rose
D. Evening primrose

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the organism on which Hugo de Vries conducted his experiments related to the mutation theory of evolution.

2. **Identifying Hugo de Vries**: Hugo de Vries was a Dutch botanist known for proposing the mutation theory, which suggests that evolution occurs through sudden and heritable changes (mutations).

3. **Publication of Mutation Theory**: De Vries published his findings in a book titled "Die Mutation Theory" in 1901, where he elaborated on his experiments and the concept of mutations.

4. **Conducting Experiments**: To understand the mechanism of evolution, de Vries performed experiments on various plants. It is essential to identify the specific plant he used for his experiments.

5. **Analyzing the Options**: The options provided are:
- A) Garden Pea
- B) Fruit Fly
- C) China Rose
- D) Evening Primrose

6. **Eliminating Incorrect Options**:
- Garden Pea: This was primarily studied by Gregor Mendel for inheritance patterns, not by de Vries.
- Fruit Fly: This organism is associated with genetic studies by Thomas Morgan, not de Vries.
- China Rose: While it is a flowering plant, it is not the one associated with de Vries's mutation theory.

7. **Identifying the Correct Answer**: The correct answer is D) Evening Primrose. This is the plant on which Hugo de Vries conducted his experiments to support his mutation theory.

8. **Conclusion**: Therefore, the answer to the question is that Hugo de Vries experimented on the Evening Primrose to explain the mechanism of evolution through his mutation theory.

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