单项选择题

下列有机物中最难被微生物降解的是( )。
A．纤维素 B．木质素 C．半纤维素 D．淀粉

A.纤维素
B.木质素
C.半纤维素

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听力原文：W: This house won't be big enough when the new baby arrives in two months. I'm afraid we have to buy a big one.
M: But I don't see we can afford it right now. We can let Andy live with my mother then.
Q: What can we learn from this conversation?
(2)
A．New baby will be born soon.
B．They will buy a big house in two months.
C．They will live with the man's mother.
D．The new baby will be sent to the man's mother.

A.
M:
B.
Q:
C.New
D.
B．They
E.
C．They
F.
D．The
G.

肺炎喘嗽患儿突然面色苍白，口唇青紫，呼吸困难，四肢厥冷，烦躁不安，右胁下出现痞块并逐渐增大，舌质略紫，苔薄白，脉细弱而数，其证候为：( )
A．心阳虚衰
B．阳气暴脱
C．邪陷厥阴
D．气滞血瘀
E．毒热闭肺

A.心阳虚衰

B.阳气暴脱

C.邪陷厥阴

D.气滞血瘀