同一只股票，其风险是客观的，但是有的人买，有的人卖，这可能是因为买者和卖者的风险认知度有差异。（）
参考答案：对
解析：
说法正确，故选A。
腰椎间盘突出症中以（ ）、（ ）间隙发病率最高。退行性腰椎滑脱发病率以（ ）间隙发病率最高。
It was not until I came here ____ I realized this place was famous for not only its beauty but also its weather.
A．who
B．that
C．where
D．before
