Select out the correct match

Options

A. Transgenic papaya - Resistant to bacterial pathogen Pseudomonas
B. Transgenic tomato - Resistant to the ring spot virus
C. Transgenic potato - Resistant to Phytophthora
D. Transgenic cotton - Resistant to nematodes

Answer

To solve the question of selecting the correct match between transgenic plants and their corresponding disease-causing organisms, we will analyze each option step by step.

### Step-by-Step Solution:

1. **Identify the Transgenic Plants and Their Corresponding Diseases:**
- We have four transgenic plants and their supposed disease-causing organisms to evaluate.

2. **Evaluate Each Option:**
- **Option 1:** Transgenic papaya resistant to bacterial pathogen *Pseudomonas*.
- This is incorrect. Transgenic papaya is actually resistant to the papaya ring spot virus, not *Pseudomonas*.

- **Option 2:** Transgenic tomato resistant to ring spot virus.
- This is also incorrect. Transgenic tomato is resistant to *Pseudomonas*, which causes bacterial speck disease, not a ring spot virus.

- **Option 3:** Transgenic potato resistant to *Phytophthora*.
- This is correct. Transgenic potato is indeed resistant to *Phytophthora*, which is a fungus that causes late blight disease in potatoes.

- **Option 4:** Transgenic cotton resistant to nematode.
- This is incorrect. Transgenic cotton is primarily resistant to insect pests, particularly bollworms, and not nematodes.

3. **Conclusion:**
- The only correct match is **Option 3:** Transgenic potato resistant to *Phytophthora*.

### Final Answer:
The correct match is **Transgenic potato resistant to *Phytophthora*.**

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