Pseudotrachea of Housefly is formed by

Options

A. Labella
B. Rostrum
C. Haustellum
D. Basiproboscis.

Answer

To answer the question "Pseudotrachea of Housefly is formed by," we will analyze the options provided and determine which one is correct.

### Step-by-Step Solution:

1. **Understanding Pseudotrachea**:
- Pseudotrachea refers to a structure in certain insects, including houseflies, that resembles tracheae (the respiratory tubes) but serves a different function.
- In houseflies, pseudotrachea are involved in the intake of liquid food.

2. **Analyzing the Options**:
- **Option 1: Labella**:
- Labella are the lobes at the end of the proboscis of a housefly. They play a crucial role in helping the fly to ingest liquid food by forming a series of tubular structures (pseudotrachea) that facilitate this process.
- **Option 2: Rostrum**:
- The rostrum is a beak-like structure but does not specifically refer to the part that forms pseudotrachea.
- **Option 3: Ostrolum**:
- This term does not relate to the anatomy of houseflies and is not relevant in this context.
- **Option 4: Bassi proboscis**:
- The term "Bassi proboscis" is not a recognized anatomical term associated with houseflies and does not refer to the structure that forms pseudotrachea.

3. **Conclusion**:
- Based on the analysis, the correct answer is **Option 1: Labella**. The labella of the housefly form the pseudotrachea, which assist in the intake of liquid food.

### Final Answer:
The pseudotrachea of housefly is formed by **Labella**.