参考答案

正确答案：B
解析：本题关键句为“Coaches and parents should be aware，at all times，that their feedback to youngsters can greatly affect their children．Youngsters may take their parents' and coaches' criticisms to heart and find a flaw in themselves．”教练和父母们的评价，尤其是批评，会对孩子产生很大的影响，孩子们会据此寻找自身的问题。由此可见，教练和父母养成批评年轻运动员的习惯，是因为他们没有意识到评判会严重损害孩子的自信心，故正确答案为B。