在影响企业发展的环境中属于社会经济结构而又最重要的因素是( )。
A.分配结构B.产业结构C.经济体制D.交换结构
参考答案:B
解析: 参见教材相关内容说明。
体内外均有抗凝作用的是()
A.肝素
B.双香豆素
C.维生素K
D.右旋糖酐
My grandfather is such a forgetful person that he has to _______ many things, even his daily meals. [ ]
A. be remembered by
B. be reminded of
C. be memorized
D. be reminded