Dear Editor,

I’m the only daughter of my parents. So they worried about everything I do. For example,

when I ride my bike, my parents won’t let me to ride by myself. They are afraid I might          

fall off  my bike and hurt myself. They are taking great trouble to support a bike, with

my mother even carried a first-aid box. I’m not free to ride and I often say angry, “Why not

let me ride alone?”Now, most family have one child. Parents want to do everything       

for his children. This does no good on them. Too many love from parents may prevent

children from independent. In my opinion, parents should let their children do that they

should do alone.           

不能通过人工培养基进行分离培养病原体的传染病是（）

A.伤寒

B.钩端螺旋体

C.脊髓灰质炎

D.霍乱

E.斑疹伤寒