This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Social & Preventive Medicine
Which of the following vectors has a habit of frequent vomiting? 
Select and explain. 
A. Sand flea, B. House fly, C. Mite, D. Mosquito
B: House fly
Answer: B: House fly 
Explanation: Housefly has a habit of frequent vomiting. The regurgitated stomach contents or "vomit drop" is a source of infection. Chapter: Environment and health Ref: Park 21st edition page: 715.