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
Commonest trophozoite infection by sexual intercourse- 
Select and explain. 
A. Entamoeba histolytica, B. Trichomonas vaginalis, C. Trepanoma palidium, D. Giardia intestinales
B: Trichomonas vaginalis
Answer: B: Trichomonas vaginalis 
Explanation: None