I ran ____ an old friend of mine yesterday, whom I hadn't seen f

I ran ____ an old friend of mine yesterday, whom I hadn't seen for ages.
A、across
B、cross
C、after
D、for
【正确答案】：A
【题目解析】：【考点点击】本题考查动词短语中介词的选择。【要点透析 run across意为“偶然遇见”,符合题意。 run after意为“追赶”; run for意为“竞选”。