题干
Yang Xiangming, ________teacher of Taizhou Experimental School, devoted his life to saving_______13-year-old boy who fell into water.
A：a, an
B：the, a
C：a, a
D：the, the
答案(点此获取答案解析）
C
与抛物线
上的点
的距离为
，
，则
取最小值时，