<prompt> Classical example of transplacental carcinogenesis is -TeratomaPrimary squamous cell carcinoma of vaginaSarcoma botryoidsClear cells adenocarcinoma of vagina  <response>: 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. 