第12题: [填空题]A be costly B be harmful C save a life D still open to debate E reduce the risk of radiation triggering a cancer F reduced to the minimum Delaying the age at which screening starts may ______. 参考答案:E 答案解析:第6段涉及这一问题如果x射线检查在50岁而不是45岁时开始,会使妇女们由于辐射而患癌症的危险减少40%到80%,所以延缓用X射线检查的年龄也许能够减少辐射诱发癌症的危险。