下列合金元素中（）会增加钢的过热倾向。
A.Si
B.Mn
C.Cr
D.V
参考答案：B
I tied the tree to the top of the stick ___it was straight .[ ]
A. in order to
B. for
C. so that
D. but
新闻心理学的研究领域（研究对象）是什么？
tree to the top of the stick ___it was straight .[ ]