食物蛋白质生物学价值的高低取决于     。           
A、蛋白质的含量
B、蛋白质的消化率
C、蛋白质的净利用率
D、必需氨基酸的含量和比值

A.建设单位
B.监理单位
C.勘测单位
D.城建单位

A．People from four different areas can have different personalities and accents.
B．People in the four countries speak the same language.
C．The U.K. is interesting because the people from the four areas belong to four different parties.

A.钢筋混凝土
B.石膏板
C.混凝土
D.砂砾