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
Drug the choice for hyperthyroidism in first trimester of pregnancy is 
Select and explain. 
A. Methimazole, B. Propylthiouraril, C. Carbimazole, D. Perchlorate
B: Propylthiouraril
Answer: B: Propylthiouraril 
Explanation: Propylthiouracil is the only thioamide which is least teratogenic and hence it is the drug of choice to hyperthyroidism in pregnancy and lactation.