RNAi technology was discovered in

Options

A. Nicotiana tobaccum
B. Caenorhabditis elegans
C. Meloidogyne incognita
D. Bacillus thuringiensis

Answer

To answer the question "RNAi technology was discovered in?", we can follow these steps:

### Step-by-Step Solution:

1. **Understand RNAi**: RNAi stands for RNA interference, a biological process where RNA molecules inhibit gene expression or translation, effectively silencing targeted genes.

2. **Identify the Organism**: RNAi technology was first discovered in a specific organism. It is crucial to know which organism this was.

3. **Research the Discovery**: The discovery of RNAi technology was made in a nematode. Specifically, it was found in the nematode worm known as *Caenorhabditis elegans*.

4. **Evaluate the Options**:
- **Option 1: Nicotiana tobacum** - This is a plant species and not where RNAi was discovered.
- **Option 2: Caenorhabditis elegans** - This is the correct nematode where RNAi technology was first discovered.
- **Option 3: Meloidogyne incognita** - This is another type of nematode but not the one where RNAi was discovered.
- **Option 4: Bacillus thuringiensis** - This is a bacterium and not related to the discovery of RNAi.

5. **Conclusion**: Based on the evaluation of the options, the correct answer is *Caenorhabditis elegans*.

### Final Answer:
RNAi technology was discovered in *Caenorhabditis elegans*.

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