This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Parasitology, Subject name: Microbiology
Trichomoniasis is transmitted through which stage: 
Select and explain. 
A. Cyst, B. Oocyst, C. Sporozoite, D. Trophozoite
D: Trophozoite
Answer: D: Trophozoite 
Explanation: Ans. D. Trophozoitea. Trichomonas vaginalis exists only as a trophozoite; no cyst stage has been identifiedb. A cyst, oocyst and sporozoite are stages involved in transmitting other protozoan infections, and an egg is the means of transmission in a number of helminth infections.