Which one of the following pairs is not correctly matched?

Options

A. Red Sea: Trichodesmium erythreum a cyanobacterium
B. Red Tides: Rhodymenia, a red algae
C. Red Snow: Chalmydomonas nivalis, a green algae
D. Red Rust of Tea: Cephaleuros virescens, a green algae

Answer

To determine which pair is not correctly matched, we will analyze each option provided in the question.

### Step-by-Step Solution:

1. **Identify the Options**: The options provided relate to various "red" phenomena and their causative agents. They include:
- Red Sea - Trichodesmium erythraeum (Cyanobacteria)
- Red Tides - Rhodomonas (Red Algae)
- Red Snow - Chlamydomonas nivalis (Green Algae)
- Red Rust of Tea - Cephaleuros virescens (Green Algae)

2. **Analyze Each Pair**:
- **Red Sea**: This is correctly matched with Trichodesmium erythraeum, a cyanobacterium that contributes to the reddish appearance of the sea due to its blooms.
- **Red Tides**: This is incorrectly matched. Red tides are caused by dinoflagellates, specifically toxic species like Karenia brevis, not Rhodomonas (which is a type of red algae).
- **Red Snow**: This is correctly matched with Chlamydomonas nivalis, a green algae that can cause a reddish tint in snow due to its pigmentation.
- **Red Rust of Tea**: This is correctly matched with Cephaleuros virescens, a green algae that acts as a parasite on tea plants.

3. **Conclusion**: The pair that is not correctly matched is the second option: Red Tides - Rhodomonas.

### Final Answer:
The pair that is not correctly matched is **Red Tides - Rhodomonas**.

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