This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General pathology, Subject name: Pathology
Classical example of transplacental carcinogenesis is - 
Select and explain. 
A. Teratoma, B. Primary squamous cell carcinoma of vagina, C. Sarcoma botryoids, D. Clear cells adenocarcinoma of vagina
D: Clear cells adenocarcinoma of vagina
Answer: D: Clear cells adenocarcinoma of vagina 
Explanation: A series of genotypic and phenotypic changes in the fetus due to utero exposure to carcinogens.. Extensive metastasis. Clear cells adenocarcinoma of vagina.. A rare type. Of cancer. Often linked to diethylselbisterol drug administration.