109型分配阀的主阀部的作用是控制（）的充气、制动、保压及紧急制动的形成.
A.车列
B.机车
C.列车
参考答案：B
资产配置的动态调整策略中，买入并持有策略属于消极型长期再平衡策略。( )
He took a seat opposite Catherine, who kept her gaze fixed on him as if she feared he would vanish were she to remove it.
