The following are multiple choice questions (with answers) about medical knowledge.   **Question:** The number of patients required in a clinical trial to treat a specify disease increases as   (A) The drop-out rate increases   (B) The significance level increases   (C) The size of the expected treatment effect increased   (D) The incidence of the disease decreases
['(A) The drop-out rate increases <> answer', 'The following are multiple choice questions (with answers) about medical knowledge. <> instruction', '(A) The drop-out rate increases \n (B) The significance level increases \n (C) The size of the expected treatment effect increased \n (D) The incidence of the disease decreases <> possible answers', '  The number of patients required in a clinical trial to treat a specify disease increases as <> context@']