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: Radiology
Medusa head appearance on abdominal X-ray indicates: 
Select and explain. 
A. Roundworm, B. Tapeworm, C. Roundworm and tape worm, D. Amoehiasis
A: Roundworm
Answer: A: Roundworm 
Explanation: Ans. Roundworm