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 is the drug of choice for malaria in a 26-year-old pregnant lady, in the first trimester? \nSelect and explain. \nA. Proguanil, B. Chloroquine, C. Aemesin, D. Halofantarine', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Chloroquine is the drug of choice for prophylaxis and treatment of malaria during all phases of pregnancy. Chloroquine is a rapidly acting blood schizonticide which destroys asexual blood forms of all plasmodium species. For woman with chloroquine-resistant infection, mefloquine is given orally.', 'role': 'assistant'}]