EBS 수능완성 5회 31번 기출 문제 빈칸 (A) (B) 채우기 Athletes who participate in track competitions usually have a favorite event in which they excel. ___(A)___, some runners prefer a short race of only 100 or 200m, while others choose a race of 1,500, 5,000, or even 10,000m. Why is it difficult to find a runner who competes equally well in both 100-m and 10,000-..