公安机关收集证据时不得有怎样的行为？
参考答案：
严禁刑讯逼供和以威胁、引诱、欺骗或者其他非法手段收集证据。以非法手段取得的证据不能作为定案的根据。
_______ the people have become masters of their country _______ science can really serve the people.
A．It is only then; that
B．It was that; when
C．It is only when; that
D．It was when; then
下列药物中，不易引起药疹的是
A．安眠镇静药
B．抗生素
C．糖皮质激素
D．解热镇痛药
E．疫苗
