Gambusia is

Options

A. Pest on fishes
B. Pathogenic fishes
C. Parasitic fish
D. Fish predator of mosquito larvae

Answer

### Step-by-Step Solution:

1. **Identify the Organism**: Gambusia is a genus of fish that belongs to the family Poecilidae.

2. **Species Classification**: There are over 40 species within this genus, with two notable ones being Gambusia affinis and Gambusia holbrookei.

3. **Habitat**: These fishes are primarily found in freshwater environments but can also inhabit brackish and saltwater areas.

4. **Common Name**: Gambusia affinis is commonly known as the "Mosquito fish." This name is significant because it reflects the fish's ecological role.

5. **Diet**: The diet of Gambusia affinis includes a large number of mosquito larvae, which is a key aspect of its behavior and ecological impact.

6. **Ecological Role**: Gambusia affinis has been introduced into various ecosystems worldwide as a biological control method to reduce mosquito populations.

7. **Final Conclusion**: Based on the information gathered, Gambusia can be classified as a fish predator of mosquito larvae.

### Final Answer:
Gambusia is a fish predator of mosquito larvae.

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