First geneticist who had an important role in the study of inheritance was

Options

A. De Vries
B. Mendel
C. Darwin
D. Morgan

Explanation

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for the name of the first geneticist who played a significant role in the study of inheritance.

2. **Recall Key Figures in Genetics**: Consider notable figures in the field of genetics and inheritance. The most prominent names include Gregor Mendel, Hugo de Vries, Charles Darwin, and Thomas Hunt Morgan.

3. **Evaluate Each Option**:
- **Hugo de Vries**: He was involved in the theories of evolution and rediscovered Mendel's laws but was not the first geneticist.
- **Charles Darwin**: Known for his theory of natural selection, but he did not specifically focus on inheritance in the way Mendel did.
- **Thomas Hunt Morgan**: He worked with fruit flies and contributed to the understanding of genetics, but he came after Mendel.

4. **Identify the Correct Answer**: Gregor Johann Mendel is recognized as the first geneticist and is often referred to as the "father of genetics." He conducted his experiments on pea plants between 1856 and 1863, establishing the foundational laws of inheritance.

5. **Conclusion**: The correct answer to the question is Gregor Johann Mendel.

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