系统的误码性能反映（）在传输过程中受到损伤的程度。
参考答案：数字信息
— How did you find your visit to the science museum. John?
— ________ [ ]
A. By taking a NO.3 bus
B. Oh, wonderful. indeed
C. I went there alone
D. A classmate of mine showed me the way
车站工作人员应严禁旅客（）。
A、钻车
B、以上都是
C、随车奔跑
D、横跨股道
