衡量人群中在短时间内新发病例的频率，采用的指标为
A．罹患率B．发病率C．患病率D．感染率E．发病比
参考答案：A
--- ____I take the newspaper to the classroom?
---No, you mustn’t. You ______ read it only here.
A．Must, can
B．May, can
C．Need, must
D．Must, must
下列繁殖方式是营养生殖的是[ ]
A．播撒玉米种子种在土壤中
B．野生水果落地后萌发出幼苗
C．用土豆的芽发育成新植株
D．埋下小麦种子后种子发芽
