Select the correct match:

Options

A. Alee Jeffreys - Streptococcus pneumoniae
B. Alfred Hershey and Martha Chase - TMV
C. Matthew Meselson and F. Stahil - Pisum sativum
D. Francois Jacob and Jacques Monod - Lac operom

Answer

To solve the question of selecting the correct match from the given options, we need to analyze each option carefully and determine which pair is accurately associated with the respective scientists and their contributions.

### Step-by-Step Solution:

1. **Option 1: Alec Jeffries - Streptococcus pneumoniae**
- Alec Jeffries is known for developing DNA fingerprinting techniques. He did not work with Streptococcus pneumoniae. Therefore, this pair is incorrect.

2. **Option 2: Alfred Hershey and Martha Chase**
- Hershey and Chase conducted the famous experiment that demonstrated that DNA is the genetic material, not protein. This pair is correctly matched.

3. **Option 3: Meselson and Stahl - PCM Sativum**
- Meselson and Stahl are known for their experiment on DNA replication, which demonstrated that DNA replication is semi-conservative. However, they used E. coli in their experiments, not PCM Sativum (which refers to pea plants). Therefore, this pair is incorrect.

4. **Option 4: Jacob and Monod - Lac Operon**
- Jacob and Monod are credited with the discovery of the lac operon, which is a model for gene regulation in bacteria. This pair is correctly matched.

### Conclusion:
After analyzing all the options, the correct match is:
- **Option 4: Jacob and Monod - Lac Operon**

### Final Answer:
The correct answer is **Option 4: Jacob and Monod - Lac Operon**.

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