Infection of Ascaris usually occurs by

Options

A. Tse-tse fly
B. mosquito bite
C. contaminated water and vegetables
D. eating imperfectly cooked pork

Answer

To solve the question "Infection of Ascaris usually occurs by," we will analyze the given options step by step.

### Step 1: Understand Ascaris
Ascaris is a type of parasitic roundworm that infects the intestines of humans. The infection is primarily caused by ingesting the eggs of the parasite.

### Step 2: Analyze the Options
We have four options to consider:
1. Cc flies
2. Muscatobite
3. Contaminated water and vegetables
4. Eating imperfectly cooked pork

### Step 3: Evaluate Each Option
- **Option 1: Cc flies**
- Cc flies are not known to transmit Ascaris. They are more associated with diseases like sleeping sickness. Therefore, this option is incorrect.

- **Option 2: Muscatobite**
- Muscatobite refers to mosquito bites. Mosquitoes are vectors for diseases such as malaria and dengue, not Ascaris. Thus, this option is also incorrect.

- **Option 3: Contaminated water and vegetables**
- Ascaris eggs are typically found in contaminated water and soil. When humans consume these contaminated sources, they can ingest the eggs, leading to infection. This option is correct.

- **Option 4: Eating imperfectly cooked pork**
- This option is misleading. Eating undercooked pork is associated with infections from other parasites, such as tapeworms, not Ascaris. Therefore, this option is incorrect.

### Conclusion
The correct answer is **Contaminated water and vegetables**.

### Final Answer
Infection of Ascaris usually occurs by **contaminated water and vegetables**.

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