415. It is the school officials who are in the best position to decide which subjects would provide the breadth and balance of a good curriculum for all students.
最有资格安排学习课程，从而让所有学生都能接受到既全面又均衡的课程教育的，莫过于学校领导。

六级词汇讲解:
本句利用it is...that/who...的强调句型突出school officials的职能。in the best position指“处于最好的位置，最有资格做某事”。连接代词which引导的名词性从句作decide的宾语。

句型拓展:
It is interpersonal skills rather than professional skills that count in your career.
对于你的事业而言，更重要的是个人交际能力，而不是专业能力。
It was not until he arrived at the station that he realized he had left his tickets at home.
直到到了车站，他才发现自己把票忘在家里了。
It was lack of money，not of effort，that defeated their plan.
导致他们的计划失败的，不是努力不够，而是缺乏资金。