预防问题行为的关键是( )。
A．端正学生的学习目的
B．建设优良的校风与班风
C．树立正确的学生观
D．改善学生的人际环境
参考答案：A
Eating more than 18 ounces of red meat per week ups your risk of colorectal cancer. Its risk also rises by 40% with every three ounces serving of process meat eating per day.
60年代日本经济起飞之后，日本加大了对（）的投入。
A、图书馆
B、国防
C、企业
D、基础设施
