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: Pharmacology
[{'content': 'Which of the following statements regarding transfer of drugs across placenta is FALSE ? \nSelect and explain. \nA. Transfer across placenta is lesser in early pregnancy, B. All drugs to some extent can cross the placenta except heparin and insulin, C. Ion trapping of acidic drugs occur in the placenta, D. P–glycoprotein is present in placenta', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Heparin and insulin are anticoagulant and antidiabetic\xa0drugs of choice, respectively in pregnancy becasue\xa0these have minimum entry across placenta\nFetal plasma is slightly more acidic than that of mother (pH 7.0 as compared to 7.4 of mother), so ion trapping of basic drugs occur.\nPlacenta contain P-glycoprotein that can act as an efflux pump for drugs.\nPlacental transfer of most drugs is greater in late pregnancy than in early pregnancy because uterine circulation increases and trophoblastic layer becomes thinner\xa0as the pregnancy advances.', 'role': 'assistant'}]