单选题 While taking a walk to the department store, I______ an old schoolmate this morning.

【正确答案】 C
【答案解析】run into意为“碰撞,遇上,偶然遇到”,符合题意;run over有“(车辆)轧过,压过,流出,溢出,匆匆看过“等意思;run to意为“钱足够支付;有足够的钱购买”或者“有……趋势”,如:He is running to fat他有发胖的趋势。