RNAi technology was discovered in

Options

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

Answer

**Step-by-Step Solution:**

1. **Understanding RNAi Technology**: RNA interference (RNAi) is a biological process in which RNA molecules inhibit gene expression or translation, effectively silencing specific genes. This is achieved through the action of double-stranded RNA (dsRNA).

2. **Discovery Context**: RNAi technology was first identified as a natural biological response to the introduction of double-stranded RNA in certain organisms, leading to gene silencing.

3. **Identifying the Organism**: The first organism in which RNA interference was discovered is the nematode worm known as *Caenorhabditis elegans*. This organism demonstrated a potent sequence-specific gene silencing response to dsRNA.

4. **Analyzing the Options**: The question provides multiple options regarding where RNAi technology was discovered. Among these options:
- Nicotiana tabacum (tobacco plant)
- *Caenorhabditis elegans* (correct answer)
- Meloidogyne incognita (a nematode affecting plants)
- Bacillus thuringiensis (a bacterium known for its insecticidal properties)

5. **Selecting the Correct Answer**: Based on the information, the correct answer is *Caenorhabditis elegans*, as it is the organism where RNA interference technology was first discovered.

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

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