Linkage was discovered by

Options

A. Punnet
B. Mendel
C. Muller
D. Morgan

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks who discovered the concept of linkage in genetics. Linkage refers to the tendency of genes located close to each other on a chromosome to be inherited together.

2. **Reviewing the Options**: The options provided are:
- 1st: Bennett
- 2nd: Mendel
- 3rd: Muller
- 4th: Morgan

3. **Analyzing Each Option**:
- **Bennett**: He is known for co-founding the Journal of Genetics and creating the Punnett square, but he did not discover linkage. Thus, this option is incorrect.
- **Mendel**: Known as the father of modern genetics, Mendel established the basic laws of inheritance through his work with pea plants. However, he did not discover the concept of linkage. Therefore, this option is also incorrect.
- **Muller**: He is recognized for his research on the effects of radiation on genetics but did not discover linkage. This option is incorrect as well.
- **Morgan**: Thomas Hunt Morgan is the scientist who coined the term "linkage" after conducting experiments with Drosophila (fruit flies). His work demonstrated that certain traits are inherited together due to their proximity on a chromosome. Thus, this option is correct.

4. **Conclusion**: The correct answer to the question "Linkage was discovered by" is **Morgan**.

**Final Answer**: Morgan

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