This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: A.N.S., Subject name: Pharmacology
Which of the following drugs is useful in prophylaxis of motion sickness? 
Select and explain. 
A. Hyoscine, B. Metoclopramide, C. Prochlorperazine, D. Ondansetron
A: Hyoscine
Answer: A: Hyoscine 
Explanation: Ans. (A) Hyoscine(Ref: KDT 8th/e p132)Hyoscine is used for the prophylaxis of motion sickness whereas other drugs listed in the question are used for the treatment of vomiting.