以下不合胆固醇的油脂是 ["A．玉米油 ","B．猪油 ","C．牛油 ","D．羊油 ","E．鸡油 "] 假设检验的基本原理是： ["A．小概率 ","B．小概率事件 ","C．小概率事件原理 ","D．反证法 ","E．以上均错"] 循证医学中，证据论证强度最高的是 ["A．描述性研究 ","B．非随机对照试验 ","C．单个随机对照试验 ","D．多个随机对照试验的系统评价"] 预防医学的主要研究对象是 ["A．动物 ","B．人群 ","C．患者 ","D．个体 ","E．以上均错"] 可能导致艾滋病病毒传播的行为是与艾滋病病人或感染者： ["A．共同进餐 ","B．共用马桶 ","C．共用游泳池 ","D．礼节性接吻 ","E．共用注射器"] 误差是指：