Lac Operon model was proposed by

Options

A. 1)Jacob-Monod
B. 2)Griffith-Avery
C. 3)Watson-Crick
D. 4)Beadle-Ephrussi

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks about the origin of the Lac Operon model, specifically who proposed it among the given options.

2. **Analyzing the Options:**
The options provided are:
- A) Jacob and Monod
- B) Griffith and Avery
- C) Watson and Crick
- D) Beadle and Tatum

3. **Identifying the Correct Answer:**
The Lac Operon model, also known as the lactose operon model, was proposed by François Jacob and Jacques Monod in 1961. They conducted significant research on the regulation of gene expression in bacteria, particularly in E. coli.

4. **Eliminating Incorrect Options:**
- Griffith and Avery are known for their work on the transformation principle in genetics, not the Lac Operon.
- Watson and Crick are famous for discovering the structure of DNA, not the Lac Operon model.
- Beadle and Tatum are known for their work on the one gene-one enzyme hypothesis, which is unrelated to the Lac Operon.

5. **Conclusion:**
Based on the information, the correct answer is A) Jacob and Monod.

**Final Answer:**
The Lac Operon model was proposed by Jacob and Monod.

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