牛传染性鼻气管炎的病型有()
A.一种
B.两种
C.三种
D.四种
E.五种
参考答案:E
She listened attentively while he poured out all his ____ for the future.
A.attempts
B.congratulations
C.belief
D.ambition
胎儿血液循环中血氧饱和度最低的部位是
A.左心房
B.左心室
C.右心房
D.脐静脉
E.脐动脉