选择人工前牙时不必考虑的因素是（）
A.剩余牙的颜色、形状和大小
B.患者过去是否戴过义齿
C.患者的面型
D.患者的肤色
E.患者的年龄
参考答案：B
Which of the following statements is TRUE for both callable and putable bonds()
A. The value of the bond is equal to the value of a similar straight bond plus the value of the option.
B. When yield volatility increases, the value of the option increases.
C. The options both benefit the bond issuer.
较重高致病性猪蓝耳病疫情由（）响应。
A.国家
B.省级
C.市级
D.县级
