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: Gynaecology & Obstetrics
[{'content': 'Which of the following perinatal infections has the highest risk of fetal infection in the first trimester: \nSelect and explain. \nA. Hepatitis B virus, B. Syphilis, C. Toxoplasmosis, D. Rubella', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]