Cockroach is -

Options

A. Not a pest but a vector of several diseases
B. A pest but not vector of any disease
C. A serious pest and vector of several diseases
D. Is neither a pest nor a vector of diseases

Answer

To determine what a cockroach is, we need to analyze the options provided and understand the characteristics of cockroaches.

### Step-by-Step Solution:

1. **Identify the Characteristics of Cockroaches**:
- Cockroaches belong to the phylum Arthropoda.
- They are known to be pests that can infest homes and food supplies.

2. **Understand the Term 'Pest'**:
- A pest is an organism that is considered harmful or destructive, particularly to crops and food supplies.
- Cockroaches are known to damage food and crops, making them a serious pest.

3. **Evaluate the Vector Concept**:
- A vector is an organism that transmits pathogens or diseases to other organisms.
- Cockroaches can carry and spread various pathogens, which can lead to diseases in humans.

4. **Analyze the Options**:
- **Option 1**: Not a pest but a vector of several diseases. (Incorrect)
- **Option 2**: A pest but not a vector of any diseases. (Incorrect)
- **Option 3**: A serious pest and a vector of several diseases. (Correct)
- **Option 4**: Neither a pest nor a vector of diseases. (Incorrect)

5. **Conclusion**:
- Based on the analysis, the correct answer is **Option 3**: Cockroach is a serious pest and a vector of several diseases.

### Final Answer:
Cockroach is a serious pest and a vector of several diseases (Option 3).

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