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搜题
【单选题】
导致菌群失调的主要原因是A.
正常菌群的定位转移
B.
细菌从无（弱）毒株突变为有（强）毒株
C.
长期使用抗生素
D.
使用免疫抑制剂
E.
微生态制剂的使用
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知识点：
皮皮学刷刷变学霸
举一反三
【单选题】He was so committed to the ______ of his faith that he was unable to evaluate them impartially.
A.
credits
B.
doctrines
C.
certificates
D.
documents
【单选题】The term paper was due to December 1, but hard as he tried, he was unable to meet the _____ for it.
A.
challenge
B.
need
C.
deadline
D.
date
【简答题】He is unable to answer the questions about the new text．He__________it yesterday．
【单选题】He was unable to make such progress, __________________.
A.
as he tried hard
B.
as hard he tried
C.
so hard did he try
D.
hard as he tried
【单选题】A multinational firm can be defined as a firm that
A.
invests short-term cash inflows in more than one currency.
B.
has sales affiliates in several countries.
C.
is incorporated in more than one country.
D.
incorporated in one country that has production and sales operations in several other countries.
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