The growth of specialization in the 19th century might be more clearly seen in sciences such as ______.

单项选择题From the last paragraph the conclusion can be drawn that ambition should be maintained ______.

单项选择题The last sentence of the first paragraph most probably implies that it is ______.

单项选择题It is generally believed that ambition may be well regarded if ______.

单项选择题Some people do not openly admit they have ambition because ______.

单项选择题Most probably the writer of this article is a ______.