参考答案：A

解析：固定搭配。根据原文“When I ran into my cousin Susan on campus，I was surprised to find that she only came up to my shoulder．”，译文为：当我在校园里偶然碰上我的表妹苏姗，我很吃惊地发现她的个子只到我的肩膀。run into固定搭配， 意思是：撞上，偶遇，come up to固定搭配，意思是：达到(标准)，比得上，所以选择a选项。She was as tall as my shoulder意思是：她和我的肩膀一般高。