This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anti-Malaria Drugs, Subject name: Pharmacology
[{'content': 'If a drug is active against the pre-erythrocytic stage of the malarial parasite it will be useful as a: \nSelect and explain. \nA. Suppressive prophylactic, B. Causal prophylactic, C. Clinical curative, D. Radical curative', 'role': 'user'}, {'content': 'Answer: B \nExplanation: If a drug is active against the pre-erythrocytic stage of the malarial parasite it will be useful as a Causal prophylactic. Stage killed Clinical Use Pre-erythrocytic Causal Prophylaxis Erythrocytic Clinical cure Suppressive Prophylaxis Exo-erythrocytic Radical cure Gametocytic Prevention of transmission', 'role': 'assistant'}]